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Machine learning-based estimation and spatial mapping of soil phosphorus and potassium using sentinel-2 and environmental covariates
Why cities cannot learn
For most of the world’s urban history, changes in policies and responses to hazards have proceeded on a timescale that made adaptation possible, however slow or politically contested. The Great Fire of London in 1666 produced building regulations within 2 years of the devastating blaze. Repeated flooding events along the Rhine and Danube Rivers through the late 20th century spurred zoning rules and hazard mapping that are now standard across Europe’s urban planning systems. What drove these improvements was a general pathway in which disruption produced evidence, evidence generated pressure, and pressure forced modifications by agencies responsible for governing a city’s well-being. However, that process has been degrading across every inhabited continent. What has emerged in its place is a volatile urbanism that is threatening resilience.
Changes in self-care, readmissions, and quality of life are associated with nurse-led telephone support in heart failure patients
Laser phase plate improves structure determination of small proteins by cryo-EM
Phase plates can, in principle, overcome the poor image contrast in cryo–electron microscopy (cryo-EM) and the resulting limits on the structural reconstruction of small proteins. However, previous designs have been unstable and compromised the high-resolution signal and have thus been unable to surpass results achieved by standard cryo-EM. Here, we show that the laser phase plate (LPP), installed in a modern, custom Titan Krios microscope, enhances the resolution in single-particle reconstruction of small proteins by improving specimen-motion correction and recovery of information from the early frames, as well as particle visualization, three-dimensional classification, and alignment. These advances use standard defocus ranges and reconstruction procedures but open the door to LPP-tailored protocols, offering further improvements by leveraging the LPP demonstrated here.
Explainable machine learning integrating environmental chemical biomarkers and maternal clinical factors for prediction of hypertensive disorder of pregnancy
US military expansion and deep-sea mining pose environmental risks to Guam
Analysis of microstructural thermo-mechanical and tribological properties of polymer composite developed with hybrid natural fibers
Abstract This study presents the development and comprehensive microstructural and mechanical characterization of a phenolic resin-based composite strengthened with lignocellulosic sisal fiber (SF), basalt fiber (BF), bio-waste cattle horn powder, graphene oxide (GO), graphite, alumina, SiC, and barite, where inclusion of hybrid natural reinforcements (SF and BF) is making this work unique. Multiple composites are fabricated using a temperature and pressure controlled hot press compression molding process with varying compositions of the composite ingredients mainly SF (2.5–10 wt%), BF (2.5–10 wt%), and GO (0.1–0.5 wt%) to capture their different combinations effect on final composite properties. The best composite (PC-T3) came up with the inclusion of 10%/10%/0.5% weight of SF/BF/GO. The flexural strength and compressive strength improvements in PC-T3 are recorded about 167% and 161% respectively as compared to neat phenolic resin (P0). PC-T3 thermal stability index also enhanced by approximately 118% as compared to P0. Dynamic mechanical analysis result confirmed a remarkable enhancement in the stiffness property of PC-T3, where its storage modulus improved by 803% approximately as compared to P0 at 300 °C, which highlights its thermo-mechanical behavior superiority. From tribological study, the composites average coefficient of friction found in the range of 0.32 to 0.45, and specific wear rate in between 3.89 × 10 − 5 to 9.27 × 10 − 5 mm 3 /N-m, where PC-T3 came up with very less specific wear rate. Further Taguchi analysis revealed that the composition is the most significant influencing factor, followed by load and sliding speed for developed composites tribological properties. Even fracture and worn surface of the composites are investigated using SEM and found improved stress transfer, a transition from matrix-dominated failure to fiber breakage and pullout, and resistance to crack propagation mechanisms in hybrid composites. The developed composite overall results confirm its potential as a sustainable alternative material for lightweight automotive friction-based applications.
Ozone erosion started decades before the ozone hole’s discovery
As bird flu threatens, New Zealand vaccinates endangered birds
Arrival of H5N1 virus on Australian mainland triggers ambitious vaccination program
Effect of scan mode and locking function on the trueness of intraoral scanners during a cut-and-rescan protocol in fixed prosthodontics
Bacteria sense virus-induced genome degradation via methylated mononucleotides
Phages often degrade the genome of their bacterial host to individual nucleotides. Here we describe Metis, a bacterial defense system that directly senses phage-mediated host genome degradation. Metis aborts phage infection once it detects the modified mono-nucleotide m 6 dAMP. As methylation of deoxyadenosines usually occurs on the DNA polymer, accumulation of m 6 dAMP signals that the host genome has been degraded. In type I Metis, sensing of m 6 dAMP activates an NAD + diphosphatase, leading to NAD + depletion and cessation of the infection process; while the effector in type II Metis is a membrane-spanning protein whose toxicity is triggered in response to the modified mono-nucleotide. We further show that Metis defense depends on endogenous DNA methylases, and that phages can escape Metis via mutations that inactivate host genome degradation.
Structural behavior of reinforced concrete beams with longitudinal voids incorporating embedded steel tubes
Abstract The integration of utility services in modern buildings often requires longitudinal openings within reinforced concrete (RC) beams. However, these voids, particularly in the compression zone, significantly reduce structural capacity and ductility by decreasing the effective concrete area and inducing stress concentrations. This study investigates the structural behavior of RC beams with longitudinal voids incorporating embedded steel tubes as internal composite reinforcement. An experimental program comprising eleven RC beams tested under four-point bending was conducted and validated using three-dimensional nonlinear finite element analysis. The study examined the effects of void geometry, tube shape, tube orientation, and reinforcement ratio. Results showed that introducing an unreinforced void reduced the ultimate load capacity by 27.5% and caused substantial losses in stiffness and energy absorption compared to the solid beam. In contrast, embedded steel tubes significantly enhanced structural performance through composite action. The best rectangular double-tube configuration increased the ultimate load capacity by 150% relative to the unreinforced void beam, while the circular double-tube system achieved an improvement of 180%. Circular tubes exhibited slightly superior performance due to more uniform stress distribution, whereas horizontally oriented rectangular tubes outperformed vertical ones because of their higher moment of inertia. The developed finite element model accurately predicted the experimental behavior and failure modes. The findings demonstrate that embedded steel tubes provide an efficient and practical solution for improving the performance of RC beams with service-integrated longitudinal voids.
Bridging data gaps to support the Global Plastics Treaty
Reporting should consider data harmonization, supply chain metrics, and pollution hotspot identification
Silicon-mediated drought tolerance in Vigna mungo through coordinated regulation of aquaporin genes, plant water relations and photosynthetic processes
Abstract Drought stress restricts growth and productivity in grain legumes, yet the integrative mechanisms underlying silicon-mediated drought tolerance in Vigna mungo (mash bean) remain poorly understood. The present study aimed to investigate the role of silicon in mitigating drought-induced damage in two mash bean cultivars. To evaluate this effect, plants were subjected to different drought regimes with and without silicon. Data on growth traits, biomass accumulation, reproductive attributes, photosynthetic gas exchange parameters, water relations, antioxidant enzyme activities, phenolic compounds, nutrient dynamics, and expression of drought-responsive genes were collected and statistically analyzed. Multivariate analyses, including PCA and structural equation modeling (SEM), were used to elucidate relationships among measured variables. Drought significantly reduced plant growth, biomass production, and reproductive traits, accompanied by marked declines in net assimilation rate (up to 35–40%), stomatal conductance, and transpiration under 25% field capacity (FC). In contrast, drought increased WUE (49.7–56.2 µmol CO₂ mmol⁻ 1 H₂O), antioxidant enzyme activities, and phenolic accumulation. Silicon supplementation substantially improved plant growth, restored photosynthetic performance, and enhanced antioxidant defense under drought conditions. Si-treated plants exhibited increased activities of SOD, CAT, and APX, higher phenolic content, improved water status, and upregulated expression of DREB2A , PIP2-1 , and TIP4-1 compared with non-supplemented plants. Multivariate analyses clearly separated drought and Si treatments, while SEM revealed strong relationships linking gene expression, biochemical defense systems, physiological processes, and plant growth responses. In conclusion, silicon supplementation significantly enhances drought tolerance in mash bean by improving photosynthetic efficiency, antioxidant capacity, and molecular regulation of water transport.
Scientists fight back against far-right plans to restrict academic freedom in Germany
Long-range extended chains arising from polymerization-driven spontaneous assembly
A central challenge for conjugated polymers is to achieve long-range order while remaining solution processable, which is essential for matching the electrical performance of their counterparts of crystalline inorganic semiconductors. In this work, we show that n-doped poly(benzodifurandione) (n-PBDF) can undergo polymerization-driven spontaneous assembly (PSA), in which chain growth, chemical doping, and structural ordering are intrinsically coupled, yielding long-range chain extension over hundreds of nanometers. We reveal that the spontaneously formed n-PBDF nanoribbons arise from a self-initiated, convergent growth mechanism driven by cooperative monomer-polymer interactions and stabilized by proton-coupled duplex chains and the polymer’s intrinsic polyelectrolyte character. With long-range extended chains in the nanoribbons, the aligned n-PBDF thin films demonstrate metallic-level conductivity (>10 4 siemens per centimeter).