Browse Articles

3D quantification of nanolites using X-ray ptychography reveals syn-eruptive nanocrystallisation impacts magma rheology

Abstract Nanoscale crystals are becoming increasingly recognised in the products of volcanic eruptions, spanning a range of magma compositions. The crystallisation of nanolites impacts magma rheology, ascent dynamics, and eruptive style. Their impact can be enhanced due to their capacity to aggregate and develop neighbouring chemically differentiated boundary layers. However, their 3D interaction, spatial distribution, and morphology is not currently understood. Here we present a cutting-edge, 3D nanometre-scale visualisation and quantification of nanolites in scoriae of the Las Sierras-Masaya basaltic Plinian eruptions, acquired using X-ray ptychography. We find that Ti-magnetite nanolites aggregate, forming elongate, irregular structures in 3D. Their crystallisation extracts Fe and Ti from the melt, resulting in differentiated boundary layers with higher viscosity. Syn-eruptive crystallisation of nanolites and their interaction is estimated to have increased magma viscosity by 2–3 orders of magnitude, therefore, they likely had a strong control on magma rheology, increasing the potential of magma fragmentation.

Prevalence, characterization and antibiogram of Staphylococcus aureus isolates from bovine and swine population in Bareilly, Uttar Pradesh, India

PAL-AI reveals genetic determinants that control poly(A)-tail length during oocyte maturation, with relevance to human fertility

Abstract In oocytes of mammals and other animals, gene regulation is mediated primarily through changes in poly(A)-tail length. Here, we introduce PAL-AI, an integrated neural network machine-learning model that accurately predicts tail-length changes in maturing oocytes of frogs and mammals. We show that PAL-AI learned known and previously unknown sequence elements and their contextual features that control poly(A)-tail length, enabling it to predict tail-length changes resulting from 3′-untranslated region single-nucleotide substitutions. It also predicted tail-length-mediated translational changes, allowing us to nominate genes important for oocyte maturation. When comparing predicted tail-length changes in human oocytes with genomic datasets of the All of Us Research Program and gnomAD, we found that genetic variants predicted to disrupt tail lengthening have been under negative selection in the human population, thereby linking mRNA tail lengthening to human female fertility.

Nanoprobe synchrotron X-ray fluorescence microscopy reveals selenium-rich spherical structure in mouse retinal pigment epithelium

Abstract High-resolution nano-focus X-ray fluorescence microscopy using hard X-rays at the European Synchrotron Radiation Facility (ESRF) IDB16 beamline detected endogenous barium, bromine, calcium, chlorine, copper, iron, manganese, potassium, phosphorus, rubidium, sulphur, selenium, strontium and zinc, at tissue, cellular and subcellular level in the outer retinal complex of light adapted, 3-week-old, male C57BL6 mice. Fresh snap-frozen (20 μm) cryosections dried at room temperature were scanned at 1 μm, 300 nm and 50 nm spatial resolution by incident X-ray photons from the synchrotron beam. Analysis of 2D maps and 3D surface plots by PyMCA and ImageJ revealed elevated zinc concentrations in the choriocapillaris (CC) (mean 45, range 28–77 ppm), retinal pigment epithelium (RPE) layer (mean 47, range 20–76 ppm), photoreceptor inner segments (RIS) ellipsoid zone, outer limiting membrane (OLM) (mean 32, range < 1–44 ppm) and outer nuclear layer (ONL) in between photoreceptor cell bodies. Mūller cells processes in ONL and their interdigitations in RIS ellipsoid zone seem to contain zinc in the cell membrane. Iron was found at elevated amounts in RIS myoid zone (mean 38, range 14–68 ppm), RPE layer (52, range 24–143 ppm), and choroid (60, range 36–172 ppm). Copper was also detected in the CC (4.3, range 1.9–9.7 ppm), RPE layer (4.5, range 1.6–20.8 ppm), and RIS myoid zone (4.9, range 1.25–10.2 ppm). Calcium was found with granular/punctate distribution in OLM (159, range 49–962 ppm), RIS myoid zone (245, range 36-1370 ppm), RPE layer (1134, range 257–2503 ppm), and CC (1101, range 323–2090 ppm). The metalloid selenium was present in the CC (1.8, range < 1-4.7 ppm] and across the RPE (basal, central, apical) (2.4, range < 1-8.5 ppm). High resolution maps of the interface photoreceptor outer segments (ROS) and the RPE apical side revealed selenium-rich spherical structures (appr. 1 μm diameter) (mean 5.6, range 2.2–8.1 ppm), associated with calcium (mean 1057, range 619–1755 ppm), phosphorus (9924, range 6118–15058 ppm), and manganese (0.7, < 1–24 ppm), surrounded by a zinc-containing layer. This study presents the first nanoprobe X-ray fluorescence microscopy image analysis of adult mouse light adapted outer retinal complex from the whole tissue to subcellular structures. The high spatial resolution (location) and high sensitivity (metal quantity) findings, together with the information on biometals available in the literature, allowed us to propose a schematic model of possible selenium biological processes and their role in physiological activities in the outer retinal complex. We hypothesise there is a dedicated selenium-rich spherical structure with the ability to cross RPE cell membranes (i.e. the outer blood retinal barrier) and with potential roles in certain biological function(s) (e.g. ROS phagocytosis by RPE cell microvilli, trans-RPE transport).

Structural convergence and water-mediated substrate mimicry enable broad neuraminidase inhibition by human antibodies

Abstract Influenza has been responsible for multiple global pandemics and seasonal epidemics and claimed millions of lives. The imminent threat of a panzootic outbreak of avian influenza H5N1 virus underscores the urgent need for pandemic preparedness and effective countermeasures, including monoclonal antibodies (mAbs). Here, we characterize human mAbs that target the highly conserved catalytic site of viral neuraminidase (NA), termed NCS mAbs, and the molecular basis of their broad specificity. Cross-reactive NA-specific B cells were isolated by using stabilized NA probes of non-circulating subtypes. We found that NCS mAbs recognized multiple NAs of influenza A as well as influenza B NAs and conferred prophylactic protections in mice against H1N1, H5N1, and influenza B viruses. Cryo-electron microscopy structures of two NCS mAbs revealed that they rely on structural mimicry of sialic acid, the substrate of NA, by coordinating not only amino acid side chains but also water molecules, enabling inhibition of NA activity across multiple influenza A and B viruses, including avian influenza clade 2.3.4.4b H5N1 viruses. Our results provide a molecular basis for the broad reactivity and inhibitory activity of NCS mAbs targeting the catalytic site of NA through substrate mimicry.

Climate-driven physiological changes in Mahseer (Tor tambroides) juveniles

Neuropeptide Y neurons mediate opioid-induced itch by disinhibiting GRP-GRPR microcircuits in the spinal cord

A novel data-driven NLMPC strategy for techno-economic microgrid management with battery energy storage under uncertainty

Abstract As renewable energy sources become more widespread and energy consumption continues to grow, there is an urgent requirement for smarter, more flexible control methods to manage microgrids (MGs) effectively. This study proposes a data-driven nonlinear model predictive control (NLMPC) framework for optimized MG operation, emphasizing energy storage system (ESS) integration. Effective MG management is crucial given increasing renewable penetration and energy demands. This framework coordinates distributed generation (DG) units, including rotating and non-rotating resources, with a battery ESS in a dynamic MG environment. Leveraging Gaussian Process Regression (GPR), the framework accurately models the complex dynamics of both DG units and the ESS. Unlike traditional model-based approaches, GPR learns system behavior from operational data, enabling precise performance prediction under varying conditions. This accuracy is crucial for optimized resource dispatch and efficient MG operation. GPR models capture ESS charging/discharging characteristics, efficiency, and state-of-charge (SOC) dynamics for informed ESS utilization. To address renewable energy uncertainties, Monte Carlo simulations are incorporated. This allows robust evaluation of the control strategy under various scenarios, ensuring MG stability and reliability despite fluctuating renewable generation. By considering these uncertainties, the NLMPC controller proactively manages DG and ESS dispatch, mitigating forecast errors and maximizing renewable energy use. The framework aims to achieve optimal power flow, balancing supply and demand while respecting operational constraints. This includes constraints on DG units, the ESS (SOC limits, charge/discharge rates), and overall MG operation (voltage and frequency stability). The NLMPC controller dynamically adjusts DG and ESS setpoints to minimize costs, maximize renewable energy use, and ensure MG stability and reliability. Simulation results demonstrate the framework’s effectiveness. Significant cost savings (approximately 39.2% compared to Conventional MPC and 41.5% compared to Adaptive MPC) and voltage stability improvements (28.57% and 52.38% respectively) are achieved. These improvements stem from accurate system dynamics modeling, robust uncertainty handling, and coordinated DG and ESS control.

Regulation of airway fumarate by host and pathogen promotes Staphylococcus aureus pneumonia

Potential effect of phyto-synthesized silver nanoparticles using Cotula cinerea Del Raw extract on salt tolerance of wheat seeds (Triticum durum desf, Boussellam variety) germination

Coastal aquifers key contributors to ocean chemistry through solute fluxes

Network pharmacology analyses and corresponding validation of the mechanistic effects of Yangyin Tongnao Granules in ischemic stroke

Brightening self-trapped exciton emission in 2D metal-organic chalcogenolates via argentophilicity-mediated anisotropic compression

Gold geochemical anomalies delineated by the stratigraphic zoning anomaly lower limit contrast method: a case study of panjiaba, Shaanxi province, China

Serological evidence of clade Ib Mpox transmission by sex workers and within household in South Kivu, DRC

Localized surface plasmon resonance sensing of hydrogen sulfide using zinc oxide film

Abstract A localized surface plasmon resonance (LSPR) sensor for hydrogen sulfide (H2S) has been developed by coating a gold nanopattern with zinc oxide (ZnO) film. H2S detection was achieved by monitoring changes in absorbance at a specific wavelength in the LSPR spectrum. The absorbance increased during exposure to H2S and remained constant after H2S ceased. These responses indicate that the sensor can measure the integrated concentrations of H2S. The sensitivity to H2S was enhanced with increasing relative humidity, enabling detection of 0.05–3 ppm H2S within 10 min at 70% relative humidity. The sensor’s sensitivity and LSPR spectrum could be restored by heating it at 500 °C in air. Notably, the sensor did not respond to methyl mercaptan or dimethyl sulfide, demonstrating high selectivity for H2S. This study highlights the potential of the ZnO-deposited LSPR sensor for highly sensitive and selective detection of H2S.

Read my LIPSS: organic lasers on micromachined resonators

Abstract Thin-film lasers based on organic semiconductors offer significant potential for miniaturized sensing and optical memory. We present a new method for creating first-order distributed feedback (DFB) Bragg gratings using laser-induced periodic surface structures (LIPSS) as the optical resonator. These subwavelength structures, fabricated via femtosecond laser micromachining, exhibit stable periodicities and provide sufficient feedback for lasing in an Alq3:DCM film. The laser emission wavelength can be widely tuned by varying the LIPSS periodicity defined by the pulse spacing of the structuring laser. While lasing is limited by LIPSS imperfections, we demonstrate that individual LIPSS gratings optically couple into a coherent macroscopic supermode. This coupling dramatically increases lasing efficiency and reduces thresholds by two orders of magnitude compared to a single LIPSS element. This straightforward fabrication enables solid-state organic DFB lasers as integrated, on-chip coherent light sources, eliminating complex external coupling into photonic circuits.

Stress granules attenuate protein nanoparticle induced osmotic imbalance via membrane potential restoration

USP17L promotes the 2-cell-like program through deubiquitination of H2AK119ub1 and ZSCAN4

Abstract In mouse, minor zygotic genome activation (ZGA) precedes and is essential for major ZGA in two-cell (2C) embryos. A subset of ZGA genes (known as “2C” genes) are also activated in a rare population of embryonic stem cells (ESCs) (2C-like cells). However, the functions of the 2C genes are not fully understood. Here, we find that one family of the 2C genes, Usp17l, plays critical roles in transcriptional and post-translational regulation of the 2C-like state in mESCs. Specifically, USP17LE, a member of the USP17L family, deubiquitinates H2AK119ub1 and promotes the expression of Dux and the downstream 2C genes and retrotransposons. Moreover, USP17LE deubiquitinates and stabilizes ZSCAN4. In mouse pre-implantation embryos, Dux is marked by strong H2AK119ub1 except for the 1-cell and early 2-cell stages. Usp17le overexpression reduces H2AK119ub1 and promotes Dux and 2C gene activation. Thus, our findings identify USP17L as a potential regulator of the 2C program.

Decomposition rate and property changes of deadwood across an altitudinal gradient: a case study in the Babia Góra Massif, Poland

Abstract The decomposition of deadwood is a key process in the biogeochemical cycle of forests, affecting water retention, soil structure and biodiversity. The aim of this study is to understand how the rate of deadwood decomposition changes depending on the location in the altitude gradient in mountain forest ecosystems. Additionally, the study investigates how the physical properties of wood vary with elevation. The experiment was conducted on the slopes of the Babia Góra Massif, where wood samples of four species (beech, fir, spruce, maple) were placed at three altitudes (800, 1000 and 1200 m above sea level). After 30 months, laboratory analyses were carried out on the density, porosity, mass loss and hydrophobicity of wood. In the case of coniferous wood (spruce and fir), the decomposition process proceeded at a similar rate across all altitudes, but more slowly compared to deciduous species. In contrast, hardwood decomposed more rapidly at lower altitudes, likely due to higher temperatures, greater microbial activity, and soil conditions more favorable to hardwood-decaying organisms. Wood decomposition led to a decrease in density and an increase in porosity, and hydrophobicity increased with altitude. The study provides new data on the dynamics of wood decomposition in the context of changing thermal and moisture conditions. The results can be used in conservation and management strategies for mountain forests.