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Livestock farms are at risk of exposure to various environmental pollutants, particularly airborne viruses that can cause infectious diseases. Hydroxyl radicals (•OH) are well-known for their strong bactericidal and virucidal properties and are widely applied in disinfection processes. However, their efficacy is significantly diminished in the presence of organic substances. This study investigated the bactericidal effects of hydroxyl radicals generated from hypochlorous acid (HOCl) under UV irradiation and evaluated their resistance to quenching by airborne organic matter. Rose Bengal (RNO) dye was used as a probe to detect •OH radical generation, while yeast extract served as a representative organic contaminant. RNO bleaching efficiency increased in a concentration-dependent manner under UV irradiation, confirming the formation of hydroxyl radicals. However, in the presence of yeast extract, this bleaching effect was drastically reduced, indicating that organic compounds can interfere with radical activity. The bactericidal effects of UV light and HOCl were independently evaluated using Salmonella as a model organism. The presence of organic matter significantly reduced the bactericidal efficacy of both UV and HOCl treatments when applied separately. In contrast, combined exposure to HOCl and UV irradiation demonstrated a 10% increase in bacterial reduction and halved the required exposure time, regardless of HOCl concentration. These findings highlight the synergistic bactericidal potential of HOCl and UV irradiation and support their applicability in airborne bacterial disinfection under realistic environmental conditions.

Differences in slab dehydration and fluid transport influence the distribution of magmatism and deep low-frequency tremors in subduction zones. Southwest Japan, particularly Kyushu and Shikoku/Chugoku, exhibits significant along-arc variation in the spatial distribution of Quaternary arc volcanoes and adakites as well as deep low-frequency tremors beneath the forearc. Using two-dimensional numerical modeling, we quantitatively evaluate melting and fluid transport via a weak hydrous layer on the slab interface since the subduction initiation to clarify the observed key differences. In Kyushu, our model shows that dehydration of the colder subducting slab is mostly completed at sub-arc depths of 80–120 km, triggering intense flux melting in the mantle wedge and an absence of sub-forearc fluid percolation for the tremors. Adakitic signature in Kyushu could be diluted by the basaltic magma in the mantle wedge which the adakitic magma traverses. Whereas the model for Shikoku/Chugoku shows shallower sub-forearc dehydration of the warmer slab (< 80 km), allowing less flux melting, slab melting for adakite, and sub-forearc fluid percolation for the tremors.

The weak slab interface controls long-term subduction dynamics. A weak hydrous layer at the slab interface promotes mechanical decoupling between the forearc mantle and the subducting slab and converts a hot forearc mantle to a cold mantle. Often referred to as a cold nose, the cold forearc mantle, plays a key role in the transition from subduction infancy to mature subduction. This study was the first to numerically demonstrate the self-consistent formation of a weak hydrous layer with permeability anisotropy based on the Southwest Japan subduction zone case, where transition-related geological features were present. Our models showed that mechanical decoupling by spontaneous downdip growth of the weak hydrous layer created a cold nose by converting a hot forearc mantle to a cold mantle. The emergence of a cold nose explained the migration of the forearc-to-arc volcanic front, expressed as the formation of mid-Miocene forearc high-magnesium andesite and Quaternary arc adakite. Furthermore, the weak hydrous layer providing a pathway for free-water transport toward the mantle wedge tip elucidates slab/mantle-derived geochemical components in deep groundwater as well as large S-wave delay times and non-volcanic seismic tremors in the forearc.

Generating quantum light emitters that operate at room temperature and at telecom wavelengths remains a significant materials challenge. To achieve this goal requires light sources that emit in the near-infrared wavelength region and that, ideally, are tunable to allow desired output wavelengths to be accessed in a controllable manner. Here, we show that exciton localization at covalently introduced aryl sp 3 defect sites in single-walled carbon nanotubes provides a route to room-temperature single-photon emission with ultrahigh single-photon purity (99%) and enhanced emission stability approaching the shot-noise limit. Moreover, we demonstrate that the inherent optical tunability of single-walled carbon nanotubes, present in their structural diversity, allows us to generate room-temperature single-photon emission spanning the entire telecom band. Single-photon emission deep into the centre of the telecom C band (1.55 µm) is achieved at the largest nanotube diameters we explore (0.936 nm). Single-photon emission with 99% purity is generated from sp 3 defects in carbon nanotubes (CNTs) by optical excitation at room temperature. By increasing the CNT diameter from 0.76 nm to 0.94 nm, the emission wavelength can be changed from 1,100 nm to 1,600 nm.

Coupled poroelastic stressing and pore-pressure accumulation along pre-existing faults in deep basement contribute to recent occurrence of seismic events at subsurface energy exploration sites. Our coupled fluid-flow and geomechanical model describes the physical processes inducing seismicity corresponding to the sequential stimulation operations in Pohang, South Korea. Simulation results show that prolonged accumulation of poroelastic energy and pore pressure along a fault can nucleate seismic events larger than M w 3 even after terminating well operations. In particular the possibility of large seismic events can be increased by multiple-well operations with alternate injection and extraction that can enhance the degree of pore-pressure diffusion and subsequent stress transfer through a rigid and low-permeability rock to the fault. This study demonstrates that the proper mechanistic model and optimal well operations need to be accounted for to mitigate unexpected seismic hazards in the presence of the site-specific uncertainty such as hidden/undetected faults and stress regime.

Subducting the buoyant crustal material of an aseismic oceanic ridge has been regarded as a dominant contributor to flat slab subduction. However, normal‐dip subduction is also observed in some cases where ridges are subducting. In this study, we compare the subduction of two ridges on the Nazca Plate: Nazca Ridge (flat slab) and Iquique Ridge (normal‐dip slab). Anisotropy determined by shear wave splitting observation suggests that the low‐velocity anomalies found beneath the ridges are mapping anisotropic structure into isotropic velocities. After a tomographic inversion incorporating anisotropy models for both ridges, we find that the low‐velocity anomalies found beneath the Nazca Ridge are not anisotropic and therefore likely represent warm mantle, and those beneath the Iquique Ridge are caused by anisotropy. We conclude that subslab mantle buoyancy has a larger impact on the subduction angle than the crustal material of the ridge. Plain Language Summary Understanding the subduction process and how the mantle flows is pivotal in understanding the planetary evolution of Earth. Yet, several subduction characteristics remain unsolved, and the angle of plate subduction, which is often categorized into <30° (shallow), ∼30–35° (normal), >35° (steep), is one of those. Subduction of an oceanic ridge on a plate has been proposed as a cause of a shallow subduction angle since the thick crust of the ridge is less dense than the surrounding mantle. However, normal angles have been observed in some cases where oceanic ridges are subducting. In this study, we compare the Nazca Ridge and the Iquique Ridge, on the Nazca Plate subducting beneath South America. The subduction angles of the Nazca and Iquique Ridges are shallow and normal, respectively. When we incorporate directional variations in seismic wave velocities, which are produced by mantle flow, in seismic tomographic imaging, we find that the subducting oceanic ridge may not be a primary factor producing shallow angle subduction. Instead, the warm mantle beneath the Nazca Ridge may provide the buoyancy to support the Nazca Plate. Comparably, since the mantle beneath the Iquique Ridge is not warm, the subduction angle would stay normal. Key Points Despite having different subduction angles, subslab low‐velocity anomalies are found beneath both Nazca Ridge and Iquique Ridge We introduced hypothetical seismic anisotropy in tomographic inversion to explore the origin of the subslab low‐velocity anomalies The low‐velocity anomalies beneath the Nazca Ridge and Iquique Ridge may come from buoyant warm mantle and anisotropy, respectively

We used local P and S waves, and regional Lg waves to investigate the Mw 4.9 Offshore Jeju Island earthquake, whose records show evidence of a complex rupture. This earthquake provides a rare window to understand the seismogenesis of moderate‐sized earthquakes on the southern Korea–East China Sea continental shelf. We computed the relative source time functions (RSTFs) by aligning the signals on the origin time of the main and its empirical Green's function (EGF) events, allowing us to use them as differential times of the EGF pair. We determined subevent locations using direct‐wave RSTFs, and captured the rupture variability of the two large subevents using waveform inversion of stacked Lg‐wave RSTFs. The first subevent rupture started by two weak nucleation phases and propagated slowly and bilaterally. Then the second subevent ruptured westward. Our analysis demonstrates that the Lg‐wave train observed at regional distances is useful in investigating detailed slip history. Plain Language Summary In‐depth studies of small‐to‐moderate‐sized earthquakes in offshore regions are often limited by sparse seismographic station coverage and a lack of close observations. Here, we demonstrate the effective use of local P and S waves and regional Lg waves to investigate the detailed rupture process of the 2021 Mw 4.9 Offshore Jeju Island, Korea earthquake. Lg wave is a guided S wave composed of a superposition of post‐critical reflections in the crust. Detailed seismological analyses using Lg waves revealed that earthquake rupture processes can be spatially complex even in areas with low seismic activity. Our analysis demonstrates that the Lg wave observed at distances greater than 150 km from the epicenter alleviates the limited local station coverage and can be a very useful signal to image the detailed slip history of the earthquake. Our analysis revealed the rupture complexity of the earthquake, expressed as a cascade of four sequential ruptures consisting of two small nucleation phases and two large subevents. Such detailed knowledge of earthquake rupture evolution is critical for understanding seismogenesis in this stable continental region setting. Key Points We demonstrate an approach to capture the complex rupture process of an offshore moderate‐sized earthquake using limited observations Direct P and S waves and Lg waves are used to image a spatiotemporal slip history of the Mw 4.9 Offshore Jeju Island, Korea earthquake Results show a cascading rupture of four subevents on a fault, offering a deeper understanding of event mechanism in low‐seismicity regions

We estimate lateral Lg wave attenuation (Q) structure at four center frequencies (0.75, 1, 2 and 2.75 Hz) along the Central California Seismic Experiment array in western US crossing the San Andreas Fault and Central Valley. We take two steps in constructing the site‐response‐corrected Lg Q model: (a) we compute relative site responses at each station using the reverse two‐station method, and (b) we estimate Q values based on the two‐station method after removing the site term. Removal of the site response in the Q model allows to probe laterally varying Q properties at mid‐to‐lower crustal depths. Our model follows a power‐law frequency dependence as Q(f)=(81±8)f(0.62±0.11)$Q(f)=(81\\pm 8){f}^{(0.62\\pm 0.11)}$ , reflecting the active tectonic setting and the presence of fluids in the region. A change in lithology from softer sediments near Pacific coast to harder basements near Sierra Nevada correlates well with the increasing trend of the Lg Q values towards east. Our laterally varying estimates at lower frequencies generally follow the variation of shear‐wave velocities at deeper crustal depth and Moho temperature, whereas those at higher frequencies mostly follow the shear‐wave velocity variation at shallow depth. Positive site responses obtained by reverse two‐station method are found at 34 stations out of total 46 stations examined, and their responses are mostly correlated with surficial lithology (i.e., sedimentary rocks) along the profile, rather than the thickness of the sediments. The site responses also exhibit a strong negative correlation to the VS30 data. Key Points Site responses at central CA are strongly affected by surface lithology and consolidation degree of sediments, rather than their thickness Lg Q values are low compared to other regions in US, reflecting tectonic activity, presence of fluid and/or soft lithology in the region Site response correction on the two‐station method enhances depth sensitivity of Lg Q estimates by suppressing surficial effects

Background The importance of corneal biomechanics in ocular health and treatments is well-recognized, but reports on associated factors are inconsistent. We established normative data for corneal stiffness using Brillouin spectroscopy in a large cohort of healthy myopic corneas, exploring potential influences on Brillouin modulus (BM) measurements. Methods Data from 1744 healthy corneas of 885 subjects (17–52 years; 422 females) were retrospectively collected, including intraocular pressure (IOP in mmHg), manifest refraction spherical equivalent (MRSE in dioptres [D]), and Pentacam measurements (central corneal thickness [CCT in µm]), K1 and K2 in D). Corneal scans were recorded on a Brillouin Optical Scanning System (BOSS ® ) using an automated 10-point pattern to measure Central, Mean, Minimum and Maximum BM values in gigapascals (GPa). Monocular data (primarily right eye) were used for correlations; binocular data for interocular comparisons. Parametric analyses included Pearson correlations, t-tests for sex differences, paired t-tests for interocular differences, and multivariate linear regression to isolate independent factors (e.g., age, sex, CCT, IOP) with interaction terms. Results Normative BM values were Central = 2.856 ± 0.053 GPa, Mean = 2.845 ± 0.038 GPa, Min = 2.819 ± 0.046 GPa, and Max = 2.885 ± 0.042 GPa. Interocular comparisons revealed statistically significant but small increases in OS compared to OD for Mean BM (0.003 GPa [95% CI: 0.001–0.005]; OD = 2.855 ± 0.038 GPa, OS = 2.858 ± 0.038 GPa; P  = 0.01) and Max BM (0.004 GPa [95% CI: 0.002–0.006]; OD = 2.886 ± 0.042 GPa, OS = 2.890 ± 0.042 GPa; P  = 0.003), as well as in K1 and CCT ( P  < 0.0001). No significant interocular differences were found in Central or Min BM ( P  ≥ 0.15). Central, Mean and Min BM values correlated significantly with CCT ( P  ≤ 0.04) but not with IOP, K1, K2, or MRSE ( P  ≥ 0.20); Max BM did not correlate with any of these clinical parameters ( P   ≥ 0.07). Males had higher BM values than females ( P  ≤ 0.006), with effect sizes (d = 0.21) and r = 0.09 –0.1. Regional mapping showed small overall differences in BM values between zones ( P  = 0.04), with slightly higher values in the Superior region. Multivariate regression confirmed independent associations: Central BM ~ age (β = 0.0008 [95% CI: 0.0001–0.0015], P  = 0.04), sex (β = 0.010 [95% CI: 0.003–0.017], P  = 0.008), CCT (β = 0.00015 [95% CI: 0.00005–0.00025], P  = 0.003); IOP was non-significant (β = 0.0004 [95% CI: −0.0008–0.0016], P  = 0.50, R ² = 0.048). Age*sex interaction was non-significant (β=−0.0002, P  = 0.62). While statistical significance was observed, the correlation coefficients were not large, suggesting a weak linear relationship. Conclusions Non-contacting Brillouin scans in a large cohort of healthy myopic eyes established robust normative BM standards, revealing associations between corneal stiffness and age, sex, and CCT. These findings provide reference values that enhance diagnostic accuracy for conditions like keratoconus and inform biomechanical assessments in refractive surgery.

Nucleoside reverse transcriptase inhibitors (NRTIs) are mainstay therapeutics for HIV that block retrovirus replication. Alu (an endogenous retroelement that also requires reverse transcriptase for its life cycle)–derived RNAs activate P2X7 and the NLRP3 inflammasome to cause cell death of the retinal pigment epithelium in geographic atrophy, a type of age-related macular degeneration. We found that NRTIs inhibit P2X7-mediated NLRP3 inflammasome activation independent of reverse transcriptase inhibition. Multiple approved and clinically relevant NRTIs prevented caspase-1 activation, the effector of the NLRP3 inflammasome, induced by Alu RNA. NRTIs were efficacious in mouse models of geographic atrophy, choroidal neovascularization, graft-versus-host disease, and sterile liver inflammation. Our findings suggest that NRTIs are ripe for drug repurposing in P2X7-driven diseases.