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To eat or to breathe?

In highland mice, the responses to low oxygen and toxins compete for a shared molecular regulator

Farmer perceptions and adaptation to agricultural water scarcity in Kondagaon district, Chhattisgarh, rural India

Coffee is under threat: how scientists are fighting to save it from extinction

The CARM1 epigenetic enzyme inhibits cross-presenting dendritic cell function in cancer immunity

The cancer-immunity cycle requires cross-presenting type I conventional dendritic cells (cDC1s) that induce T cell–mediated immunity, but therapeutic strategies for enhancing intratumoral cDC1 function are currently inadequate. We found the epigenetic enzyme CARM1 (coactivator-associated arginine methyltransferase 1) to be a selective negative regulator of cancer antigen presentation by cDC1s but not cDC2s. Inactivation of the Carm1 gene promoted cDC1 antigen cross-presentation, activation, and accumulation in tumors, and a CARM1 inhibitor enhanced cDC1-mediated priming of T cells by means of a cancer neoantigen vaccine. CARM1 inhibition increased chromatin accessibility at BATF3-Jun and RelA sites that are critical for cDC1 function and activation. Transforming growth factor–β regulated Carm1 expression, which suggests that CARM1 inactivation enhanced intratumoral cDC1 function without altering cDC1 homeostasis. These studies identify CARM1 as a potential therapeutic target for enhancing the antitumor function of mouse and human cDC1s.

Strategies to reduce osmotic stress during cryopreservation of red blood cells when using trehalose

Abstract The aim of this study was to determine optimal conditions for cryopreserving red blood cells (RBCs) using trehalose. We assessed the extent of trehalose uptake by RBCs during incubation at 37 °C and following freezing-and-thawing. Additionally, we examined whether betaine could alleviate osmotic stress at various stages of the cryopreservation process, including trehalose loading, freezing, and return to isotonic conditions after thawing. Trehalose uptake during incubation at 37 °C was limited, whereas freezing-and-thawing RBCs in trehalose-containing solutions led to substantially higher intracellular trehalose concentrations. The greatest post-thaw survival was observed with 400 mM trehalose in combination with rapid cooling. When trehalose was combined with betaine, optimal cryosurvival was maintained at a total solute concentration of 400 mM, whereas supplementing 400 mM trehalose with membrane-permeating cryoprotectants such as glycerol or dimethyl sulfoxide (DMSO) further enhanced cell cryosurvival. Membrane permeability studies indicated that betaine acts as a non-permeating solute contradicting literature findings. Direct transfer of trehalose-loaded, cryopreserved RBCs to isotonic conditions after thawing resulted in hemolysis, but this could be reduced by using hypertonic washing solutions. In conclusion, no synergistic protective effect was observed from combining betaine with trehalose for RBC cryopreservation, whereas combinations of trehalose with membrane-permeating agents like glycerol or DMSO appear promising for improving RBC cryopreservation outcomes.

Vicinal disubstitution of alkyl C–X synthons via alkene radical cation generation

In organic chemistry, functionalization of two adjacent carbons often starts from alkenes or already disubstituted precursors. Herein, we report an exergonic activation mode that directly generates alkene radical cation intermediates from monofunctional C(sp 3 )–X handles through a photoredox-triggered hydrogen-atom abstraction (HAT) and spin-center shift (SCS) process. Computations show that electron delocalization and a network of hydrogen-bonding solvent molecules facilitate a concerted [HAT+SCS] mechanism. The catalytic platform was used to design a transfer of electrophilic reactivity (C–X) from one carbon to another, which we refer to as electrophilic shuttling. Thus, two nucleophiles can be used in the construction of 1,2-difunctionalization adducts from homobenzylic C–X synthons, delivering bisazole architectures and demonstrating compatibility with other nucleophile classes. A suite of transformations is developed that departs from conventional synthetic logic, for which alkyl C–X scaffolds are confined to single-site substitutions, now transforming them into nonintuitive precursors for building vicinal complexity.

Neural pattern stability within events is similar in young and older adults

Virome-wide ubiquitin ligase discovery reveals diverse mechanisms of immune evasion

Viruses are intracellular parasites that reprogram the host proteome to promote replication and evade immune recognition. We applied a virome-wide library of ~10,000 open reading frames to discover viral ubiquitin ligases, mapping their mechanisms of degradation and host substrates using targeted CRISPR screens and proteomics. These viral effectors could be classified as canonical ligases that mimic host E3s, hijackers that redirect host E3s, and non-canonical ligases that rewire Cullin-RING ligase machinery. These diverse strategies of virus-mediated degradation converged on immune-related substrates, including JAK1 and CUL1 β−TrCP , underscoring immune evasion as a major driver of viral ubiquitin ligase evolution. Our findings elucidate viral strategies for exploiting the ubiquitin–proteasome system with potential for therapeutic targeting.

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.