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Plasmonic nanoparticle-based biosensors often report a colorimetric signal through the aggregation or clustering of the nanoparticles (NPs), but these mechanisms typically struggle to function in complex biofluids. Here, we report a matrixinsensitive sensor array approach to detect bacteria, fungi, and viruses whose signal is based on the dissociation of the peptideaggregated NPs by thiolated polyethylene glycol (HS-PEG) polymers. We show that the HS-PEGs of differing sizes have varying capabilities to dissociate citrate-capped gold nanoparticle (AuNP) and silver nanoparticle (AgNP) assemblies. The dissociative abilities of the HS-PEGs were used in this sensor array to discriminate at the 90% confidence level the microorganisms Porphyromonas gingivalis, Fusobacterium nucleatum, and Candida albicans in water and saliva using linear discriminant analysis (LDA). We further demonstrate the versatility of the sensor array by detecting various subtypes of the viruses SARS-CoV-2 (beta, delta, and omicron) and influenza (H3N2) spiked in saliva samples using LDA. In the final demonstration, the sensor array design stratified healthy saliva samples from patient samples diagnosed with periodontitis as well as COVID-19. 

Cells interact as dynamically evolving ecosystems. While recent single-cell and spatial multi-omics technologies quantify individual cell characteristics, predicting their evolution requires mathematical modeling. We propose a conceptual framework—a cell behavior hypothesis grammar—that uses natural language statements (cell rules) to create mathematical models. This enables systematic integration of biological knowledge and multi-omics data to generate in silico models, enabling virtual “thought experiments” that test and expand our understanding of multicellular systems and generate new testable hypotheses. This paper motivates and describes the grammar, offers a reference implementation, and demonstrates its use in developing both de novo mechanistic models and those informed by multi-omics data. We show its potential through examples in cancer and its broader applicability in simulating brain development. This approach bridges biological, clinical, and systems biology research for mathematical modeling at scale, allowing the community to predict emergent multicellular behavior. 

Abstract Hydroxylation of wadsleyite, β-(Mg,Fe)2SiO4, is associated with divalent cation defects and well known to affect its physical properties. However, an atomic-scale understanding of the defect structure and hydrogen bonding at high pressures is needed to interpret the influence of water on the behavior of wadsleyite in the mantle transition zone. We have determined the pressure evolution of the wadsleyite crystal symmetry and structure, including all O∙∙∙O interatomic distances, up to 32 GPa using single-crystal X-ray diffraction on two well-characterized, Fe-bearing (Fo90) samples containing 0.25(4) and 2.0(2) wt% H2O. Both compositions undergo a pressure-dependent monoclinic distortion from orthorhombic symmetry above 9 GPa, with the less hydrous sample showing a larger increase in distortion at increased pressures due to the difference in compressibility of the split M3 site in the monoclinic setting arising from preferred vacancy ordering at the M3B site. Although hydrogen positions cannot be modeled from the X-ray diffraction data, the pressure evolution of the longer O1∙∙∙O4 distance in the structure characterizes the primary hydrogen bond length. We observe the hydrogen-bonded O1∙∙∙O4 distance shorten gradually from 3.080(1) Å at ambient pressure to about 2.90(1) Å at 25 GPa, being still much longer than is defined as strong hydrogen bonding (2.5–2.7 Å). Above 25 GPa and up to the maximum pressure of the experiment at 32.5 GPa, the hydrogen-bonded O1∙∙∙O4 distance decreases no further, despite the fact that previous spectroscopic studies have shown that the primary O-H stretching frequencies continuously drop into the regime of strong hydrogen bonding (<3200 cm–1) above ~15 GPa. We propose that the primary O1-H∙∙∙O4 hydrogen bond in wadsleyite becomes highly nonlinear at high pressures based on its deviation from frequency-distance correlations for linear hydrogen bonds. One possible explanation is that the hydrogen position shifts from being nearly on the long O1-O4 edge of the M3 site to a position more above O1 along the c-axis. 

Nurses face significant physical demands during patient care, leading to high rates of musculoskeletal disorders (MSDs) among nurses in long-term care. Exoskeletons demonstrate promise in supporting nurses and nurse managers with MSDs; however, social contextual factors are crucial to their design and implementation. Through thematic analysis of 17 semi-structured interviews, this paper reveals social contextual factors important to exoskeleton use among nurses and nurse managers in long-term care. Participants expressed concerns about workplace discrimination, co-worker perceptions of their capabilities, and patient confidence. Our findings highlight the need for supportive organizational cultures and open communication channels. Recommendations include in-depth systems analysis to assess exoskeleton feasibility and efficacy, involving input from frontline nurses/managers, management, and patients. These findings can aid human factors and ergonomics (HF/E) experts in balancing social contextual factors and other work system elements to design work system contexts and exoskeletons that promote optimal outcomes in long-term care settings. 

Using first-principles calculations, this study evaluates the structure, equation of state, and elasticity of three compositions of phase D up to 75 GPa: (1) the magnesium endmember [MgSi2O4(OH)2], (2) the aluminum endmember [Al2SiO4(OH)2], and (3) phase D with 50% Al-substitution [AlMg0.5Si1.5O4(OH)2]. We find that the Mg-endmember undergoes hydrogen-bond symmetrization and that this symmetrization is linked to a 22% increase in the bulk modulus of phase D, in agreement with previous studies. Al2SiO4(OH)2 also undergoes hydrogen-bond symmetrization, but the concomitant increase in bulk modulus is only 13%—a significant departure from the 22% increase of the Mg-endmember. Additionally, Al-endmember phase D is denser (2%–6%), less compressible (6%–25%), and has faster compressional (6%–12%) and shear velocities (12%–15%) relative to its Mg-endmember counterpart. Finally, we investigated the properties of phase D with 50% Al-substitution [AlMg0.5Si1.5O4(OH)2], and found that the hydrogen-bond symmetrization, equation of state parameters, and elastic constants of this tie-line composition cannot be accurately modeled by interpolating the properties of the Mg- and Al-endmembers. 

Ocean surface radiation measurement best practices have been developed as a first step to support the interoperability of radiation measurements across multiple ocean platforms and between land and ocean networks. This document describes the consensus by a working group of radiation measurement experts from land, ocean, and aircraft communities. The scope was limited to broadband shortwave (solar) and longwave (terrestrial infrared) surface irradiance measurements for quantification of the surface radiation budget. Best practices for spectral measurements for biological purposes like photosynthetically active radiation and ocean color are only mentioned briefly to motivate future interactions between the physical surface flux and biological radiation measurement communities. Topics discussed in these best practices include instrument selection, handling of sensors and installation, data quality monitoring, data processing, and calibration. It is recognized that platform and resource limitations may prohibit incorporating all best practices into all measurements and that spatial coverage is also an important motivator for expanding current networks. Thus, one of the key recommendations is to perform interoperability experiments that can help quantify the uncertainty of different practices and lay the groundwork for a multi-tiered global network with a mix of high-accuracy reference stations and lower-cost platforms and practices that can fill in spatial gaps. 

Abstract. In early 2020, an international team set out to investigatetrade-wind cumulus clouds and their coupling to the large-scale circulationthrough the field campaign EUREC4A: ElUcidating the RolE ofClouds-Circulation Coupling in ClimAte. Focused on the western tropicalAtlantic near Barbados, EUREC4A deployed a number of innovativeobservational strategies, including a large network of water isotopicmeasurements collectively known as EUREC4A-iso, to study the tropicalshallow convective environment. The goal of the isotopic measurements was toelucidate processes that regulate the hydroclimate state – for example, byidentifying moisture sources, quantifying mixing between atmospheric layers,characterizing the microphysics that influence the formation and persistenceof clouds and precipitation, and providing an extra constraint in theevaluation of numerical simulations. During the field experiment,researchers deployed seven water vapor isotopic analyzers on two aircraft,on three ships, and at the Barbados Cloud Observatory (BCO). Precipitationwas collected for isotopic analysis at the BCO and from aboard four ships.In addition, three ships collected seawater for isotopic analysis. All told,the in situ data span the period 5 January–22 February 2020 andcover the approximate area 6 to 16∘ N and 50 to 60∘ W,with water vapor isotope ratios measured from a few meters above sea levelto the mid-free troposphere and seawater samples spanning the ocean surfaceto several kilometers depth. This paper describes the full EUREC4A isotopic in situ data collection– providing extensive information about sampling strategies and datauncertainties – and also guides readers to complementary remotely sensedwater vapor isotope ratios. All field data have been made publicly availableeven if they are affected by known biases, as is the case for high-altitudeaircraft measurements, one of the two BCO ground-based water vapor timeseries, and select rain and seawater samples from the ships. Publication ofthese data reflects a desire to promote dialogue around improving waterisotope measurement strategies for the future. The remaining, high-qualitydata create unprecedented opportunities to close water isotopic budgets andevaluate water fluxes and their influence on cloudiness in the trade-windenvironment. The full list of dataset DOIs and notes on data quality flagsare provided in Table 3 of Sect. 5 (“Data availability”). 

Abstract Constraining the accommodation, distribution, and circulation of hydrogen in the Earth's interior is vital to our broader understanding of the deep Earth due to the significant influence of hydrogen on the material and rheological properties of minerals. Recently, a great deal of attention has been paid to the high-pressure polymorphs of FeOOH (space groups P21nm and Pnnm). These structures potentially form a hydrogen-bearing solid solution with AlOOH and phase H (MgSiO4H2) that may transport water (OH–) deep into the Earth's lower mantle. Additionally, the pyrite-type polymorph (space group Pa3 of FeOOH), and its potential dehydration have been linked to phenomena as diverse as the introduction of hydrogen into the outer core (Nishi et al. 2017), the formation of ultralow-velocity zones (ULVZs) (Liu et al. 2017), and the Great Oxidation Event (Hu et al. 2016). In this study, the high-pressure evolution of FeOOH was re-evaluated up to ~75 GPa using a combination of synchrotron-based X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and optical absorption spectroscopy. Based on these measurements, we report three principal findings: (1) pressure-induced changes in hydrogen bonding (proton disordering or hydrogen bond symmetrization) occur at substantially lower pressures in ε-FeOOH than previously reported and are unlikely to be linked to the high-spin to low-spin transition; (2) ε-FeOOH undergoes a 10% volume collapse coincident with an isostructural Pnnm → Pnnm transition at approximately 45 GPa; and (3) a pressure-induced band gap reduction is observed in FeOOH at pressures consistent with the previously reported spin transition (40 to 50 GPa).