Radar studies produce contradictory results, raising questions about efforts to identify areas vulnerable to rising seas.Radar studies produce contradictory results, raising questions about efforts to identify areas vulnerable to rising seas.
Mechanical metamaterials exploit precise control of unit-cell geometry and their macroscopic organization to realize unusual properties. Expanding the capabilities of mechanical metamaterials to incorporate additional fu...Mechanical metamaterials exploit precise control of unit-cell geometry and their macroscopic organization to realize unusual properties. Expanding the capabilities of mechanical metamaterials to incorporate additional functionality remains a challenge. We describe 3D-printed metamaterials embedded with molecular ferroelectrics for use as self-powered pressure sensors. Our gradient lattice design allows for adaptive reconfiguration and controlled deformation-mode transitions, yielding a synergy of low modulus and high load-bearing capacity alongside a monotonic mechanical load-electrical signal response. Furthermore, we implement a modulus gradient in the metamaterials to enhance sensitivity in low-loading regions and extend the detection range across six orders of magnitude. With a combination of high sensitivity and broad detection range, the dual-gradient metamaterials overcome the limitations imposed by the inverse relationships in existing sensors.
Reilly PF, Rong S, Tejada-Martinez D
… +12 more, Miller SL, Tjahjadi A, Liu C, Akers J, Pomer A, Prentice ME, Merriwether DA, Friedlaender FR, Koki G, Friedlaender JS, Reilly SK, Tucci S
Near Oceanic populations harbor substantial cultural, phenotypic, and genetic diversity yet are drastically underrepresented in human genomics. We generated 177 high-coverage Near Oceanian whole genomes and analyzed them...Near Oceanic populations harbor substantial cultural, phenotypic, and genetic diversity yet are drastically underrepresented in human genomics. We generated 177 high-coverage Near Oceanian whole genomes and analyzed them alongside 1284 worldwide genomes, revealing major distinctions among and within islands, including long-term isolation and strong population bottlenecks. We reconstructed 1.897 billion base pairs of the archaic genome, including 831.9 million base pairs of Denisovan sequence, and found evidence for introgression from three Denisovan-like groups in Near Oceanians and adaptive Denisovan introgression at , a skeletal development gene also under selection in central African rainforest hunter-gatherers and highland Ecuadorians. We then performed a massively parallel reporter assay and discovered 3127 high-frequency introgressed expression-modulating variants, finding an enrichment of functional impacts on genes in the interferon-γ signaling pathway including , , and .
Large-scale artificial intelligence training demands ultralow-latency, energy-efficient interconnects for massive graphics processing unit clusters. In intensity-modulation/direct-detection links, digital signal processi...Large-scale artificial intelligence training demands ultralow-latency, energy-efficient interconnects for massive graphics processing unit clusters. In intensity-modulation/direct-detection links, digital signal processing (DSP) equalization is limited by nonideal equalization caused by phase loss as well as tight power and latency budgets. We present an integrated, programmable optical signal processor (OSP) that functions as a nonlinear universal equalizer and performs all-optical, DSP-free, real-time equalization. A deep reservoir with all-optical readout enables a Vernier scheme with ~1-picosecond (ps) sampling resolution and a tunable memory window. The OSP simultaneously equalizes eight wavelength-division-multiplexing (WDM) channels, delivering 1.6-terabits/second aggregate throughput with <60-picoseconds latency and tens of femtojoules/bit energy consumption. Operating before detection, it provides superior chromatic dispersion compensation, mitigates transceiver bandwidth limits and fiber nonlinearity, and expands the usable WDM window by a factor of 6.8.
Labor is mediated proximately by prostaglandin signaling within gestational tissues and must be tightly regulated for birth to occur after appropriate fetal development. Metabolic changes accompanying gestational aging h...Labor is mediated proximately by prostaglandin signaling within gestational tissues and must be tightly regulated for birth to occur after appropriate fetal development. Metabolic changes accompanying gestational aging have been postulated as a determinant of birth timing, but specific nutrients, sensors, and messengers remain obscure. We report that placental nicotinamide adenine dinucleotide (NAD) dynamically tunes gestational length. Depletion of placental NAD in mice provoked labor onset, mediated by the role of NAD as a cofactor for 15-hydroxy prostaglandin dehydrogenase, an enzyme responsible for suppressing prostaglandin accumulation. Augmentation of placental NAD prolonged gestation at baseline and in a model of preterm labor. These findings suggest a central role for metabolic exhaustion in provoking labor and reveal potential therapeutic avenues for preterm labor and the optimization of labor induction.
Wildfires are reversing decades of air quality improvements across much of the US. Expanded use of prescribed fire is a primary proposed solution, but air quality trade-offs-more initial smoke for less smoke later-remain...Wildfires are reversing decades of air quality improvements across much of the US. Expanded use of prescribed fire is a primary proposed solution, but air quality trade-offs-more initial smoke for less smoke later-remain poorly quantified. Using two decades of satellite-derived measurements of fire severity and smoke particulate matter across California, we assessed the causal effect of low-severity wildfire, a proxy for prescribed burning, on subsequent wildfire activity and air quality. We found that low-severity fire reduced the probability of very-high-severity wildfire by 92%, with reductions lasting a decade and extending 5 kilometers from treated locations. Reduced future smoke far outweighed the smoke produced during treatment, with benefit-cost ratios exceeding five after a decade. Sustained treatment of 500,000 acres annually would reduce cumulative smoke fine particulate matter (PM) by about 10% after a decade.
A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.A weekly roundup of information on newly offered instrumentation, apparatus, and laboratory materials of potential interest to researchers.
Improved rangeland grazing could mitigate climate change through carbon dioxide (CO) sequestration in soils and vegetation. However, altering grazing practices to increase ecosystem carbon storage may also decrease lives...Improved rangeland grazing could mitigate climate change through carbon dioxide (CO) sequestration in soils and vegetation. However, altering grazing practices to increase ecosystem carbon storage may also decrease livestock production and/or increase greenhouse gas emissions through the supply chain, such that the net emissions impacts remain unclear. Here, we assess the global net mitigation potential of improving grazing intensity by quantifying potential CO sequestration alongside systems-level impacts of plant productivity changes, livestock emissions, feed requirements, and production constraints. Improving grazing intensity in global rangelands could sequester 2.2 ± 0.43 gigatons of carbon dioxide equivalent (Gt/COeq) per year in the near term, but maintaining livestock production through supplemental feeding would reduce net mitigation by 2 to 31% (to 1.8 ± 0.45 GT/COeq per year). Our results suggest that neglecting systems-level emissions impacts may substantially overestimate the global climate benefits of improved grazing.
Marek S, Donohue MR, Karcher NR
… +33 more, Hoyniak CP, Chauvin RJ, Meyer AC, Miller J, Van AN, Wang A, Baden NJ, Suljic V, Scheidter KM, Monk J, Whiting FI, Ramirez-Perez NJ, Krimmel SR, Metoki A, Paul SE, Gorelik AJ, Hendrickson TJ, Malone SM, Schwarzlose RF, Cardenas-Iniguez C, Herting MM, Petersen SE, Luby J, Randolph AC, Shanahan MJ, Turkheimer E, Kay BP, Gordon EM, Laumann TO, Barch DM, Fair DA, Tervo-Clemmens B, Dosenbach NUF
Previous brain-wide association studies (BWAS) have linked specific environmental and behavioral variables to brain variability. In this work, we mapped 649 variables to children's brains and compared the resultant BWAS...Previous brain-wide association studies (BWAS) have linked specific environmental and behavioral variables to brain variability. In this work, we mapped 649 variables to children's brains and compared the resultant BWAS maps with each other and with neurobiological reference patterns. Socioeconomic status (SES) showed the strongest brain-wide associations. The SES associations were strongest in motor and sensory but not cognitive regions, a pattern shared across many BWAS maps, including intelligence quotient (IQ). A single, common BWAS brain pattern existed across variables that was most reflective of a child's socioeconomics. Adjusting for SES weakened brain-IQ associations, eliminating the BWAS motor and sensory pattern. Brain-with-IQ associations also did not generalize when trained on higher-SES subsamples. Thus, children's brains vary the most with SES, potentially through SES-dependent sleep deprivation and stress.
After decades of warnings, new data suggest the Atlantic Ocean's vital circulation may withstand climate warming better than feared.After decades of warnings, new data suggest the Atlantic Ocean's vital circulation may withstand climate warming better than feared.
Hsieh P, Soisangwan N, Gordon DS
… +13 more, Javidh A, Harvey WT, Porubsky D, Hoekzema K, Baker C, Munson KM, Kinipi C, Leavesley M, Brucato N, Cox MP, Ricaut FX, Romero IG, Eichler EE
Genetic introgression from Neanderthals and Denisovans shaped modern human genomes; however, introgressed structural variants (SVs ≥ 50 base pairs) remain challenging to discover. We integrated high-quality phased assemb...Genetic introgression from Neanderthals and Denisovans shaped modern human genomes; however, introgressed structural variants (SVs ≥ 50 base pairs) remain challenging to discover. We integrated high-quality phased assemblies from four new Papua New Guinea (PNG) haploid genomes with 94 published assemblies of diverse ancestry to infer an introgressed SV map. Introgressed SVs are enriched in genes (47%), including critical genomic disorder regions, and are most abundant in PNG genomes. We identified 11 centromeres likely derived from archaic hominins, adding unexplored diversity to centromere genomics. Pangenome genotyping of these 98 assemblies across 1363 samples revealed 16 adaptive SVs, many associated with immune-related genes and expression, in the PNG genomes. We hypothesize that archaic SVs contributed to reproductive success, underscoring introgression as a major force in human adaptive evolution.
Plants can move rapidly without muscles, as seen in the Venus flytrap's snapping lobes-a long-standing puzzle in plant biomechanics. Trap closure involves an elastic instability, but the active mechanical driver has rema...Plants can move rapidly without muscles, as seen in the Venus flytrap's snapping lobes-a long-standing puzzle in plant biomechanics. Trap closure involves an elastic instability, but the active mechanical driver has remained elusive. Using in situ hydraulic and mechanical measurements, we identified the motor driving this transition. Closure occurs too quickly to be explained by water transport, revealing a distinct, nonhydraulic mechanism: a rapid (about one second) softening of the epidermal cell wall, releasing elastic energy stored in the trap. This represents the fastest modulation of wall mechanics reported in plants. Our finding reveals a mode of plant motility based on dynamic tuning of material properties, suggesting principles for muscle-free, bioinspired actuation.
In a debate that has been building for years, a growing coalition of reformers has concluded that the research project grant (RPG) approach used by many science funders in the United States and based on competitive, inve...In a debate that has been building for years, a growing coalition of reformers has concluded that the research project grant (RPG) approach used by many science funders in the United States and based on competitive, investigator-initiated, and peer-reviewed proposals cannot support transformative science. Crystallizing this debate, the US National Science Foundation (NSF) has just committed $1.5 billion over the next decade to X-Labs, independent and milestone-driven research organizations meant to bypass not only the RPG but also the universities that have long been its principal recipients. Although the reform impulse may warrant sympathy, the X-Labs prescription merits skepticism.
Geng Hongwei's investigations into prominent Chinese scientists have triggered unusually swift responses.Geng Hongwei's investigations into prominent Chinese scientists have triggered unusually swift responses.
Many exoplanets have been observed with radius sizes between that of Earth and that of Neptune and are thus classified into two groups: super-earths (SEs) and mini-neptunes (MNs). There are no SEs or MNs in the Solar Sys...Many exoplanets have been observed with radius sizes between that of Earth and that of Neptune and are thus classified into two groups: super-earths (SEs) and mini-neptunes (MNs). There are no SEs or MNs in the Solar System, and the mechanisms responsible for their formation and evolution are debated. We investigated the relationships between the orbital period and eccentricity of SEs and MNs using both ensemble statistical analyses and individual measurements. We found that MNs follow an anticorrelation between orbital period and eccentricity, but SEs follow a different relation, possibly in the opposite direction. These trends imply that MNs and SEs are dynamically distinct populations. We suggest that SEs have been more strongly influenced by violent processes such as gravitational scattering and giant impacts, whereas MNs predominantly experienced quiescent secular evolution.
Cancer and cell-aging studies may have relied on antibodies to incorrect molecule.Cancer and cell-aging studies may have relied on antibodies to incorrect molecule.
Kandyba E, Jabouille A, Calvet F
… +15 more, Li YR, Curtabbi A, Cristea D, Shin J, Delrosario R, Anzules J, Wu D, Quigley D, Taylor M, Zanette C, Lo FY, Higgins J, Salk J, Lopez-Bigas N, Balmain A
The identification of the cancer cell of origin is a fundamental question in cancer biology. We used fluorescent lineage tracing of independent mouse skin stem cell populations, single cell transcriptomics, and Duplex se...The identification of the cancer cell of origin is a fundamental question in cancer biology. We used fluorescent lineage tracing of independent mouse skin stem cell populations, single cell transcriptomics, and Duplex sequencing, to identify the origin of chemically induced skin tumors. Tumors arose predominantly from and / or stem cells of the upper hair follicle, but only very rarely from the + and + hair follicle bulge. + stem cells initiated by dimethylbenzanthracene responded to tumor promoter treatment resulting in clonal expansion of initiated cells carrying the canonical Q61L mutation. Spontaneous mutations in also clonally expanded, but did not generate tumors unless the gene was deleted, thus revealing a competitive interaction between and pathways that influences clonal selection.