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1. Recruitment and Collection of Dermal Interstitial Fluid Using a Microneedle Patch

   https://doi.org/10.1002/adhm.201801262  

   Kolluru, Chandana ; Williams, Mikayla ; Chae, Jeremy ; Prausnitz, Mark R. ( January 2019 , Advanced Healthcare Materials)

   Interstitial fluid (ISF) that surrounds cells in tissues of the body is a novel source of biomarker that complements conventional sources like blood, urine, and saliva. To overcome difficulties in harvesting ISF, a minimally invasive, rapid, simple‐to‐use, cost‐effective method is developed to collect ISF from the skin involving a microneedle (MN) patch. By pressing 650 µm long MNs at an angle just below the skin surface, blood‐free ISF flows through micropores to the skin surface and is absorbed into a thin strip of paper on the MN patch backing for subsequent analysis. An optimized method in rat skin in vivo is well tolerated and able to collect >2 µL of ISF within 1 min. Brief skin pretreatment with MNs followed by a 5 min delay dramatically increases subsequent ISF collection by a mechanism believed to involve increased skin hydration. ISF collection using an MN patch has the potential to simplify access to biomarkers in ISF for research and future medical diagnostic and monitoring applications.

    

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2. Multiphase ISM in the z = 5.7 Hyperluminous Starburst SPT 0346–52

   https://doi.org/10.3847/1538-4357/ac58f9  

   Litke, Katrina C. ; Marrone, Daniel P. ; Aravena, Manuel ; Béthermin, Matthieu ; Chapman, Scott C. ; Dong, Chenxing ; Hayward, Christopher C. ; Hill, Ryley ; Jarugula, Sreevani ; Malkan, Matthew A. ; et al ( April 2022 , The Astrophysical Journal)

   With Σ_SFR∼ 4200M_⊙yr⁻¹kpc⁻², SPT 0346–52 (z= 5.7) is the most intensely star-forming galaxy discovered by the South Pole Telescope. In this paper, we expand on previous spatially resolved studies, using ALMA observations of dust continuum, [Nii] 205μm, [Cii] 158μm, [Oi] 146μm, and undetected [Nii] 122μm and [Oi] 63μm emission to study the multiphase interstellar medium (ISM) in SPT 0346–52. We use pixelated, visibility-based lens modeling to reconstruct the source-plane emission. We also model the source-plane emission using the photoionization codecloudyand find a supersolar metallicity system. We calculateT_dust= 48.3 K andλ_peak= 80μm and see line deficits in all five lines. The ionized gas is less dense than comparable galaxies, withn_e< 32 cm⁻³, while ∼20% of the [Cii] 158μm emission originates from the ionized phase of the ISM. We also calculate the masses of several phases of the ISM. We find that molecular gas dominates the mass of the ISM in SPT 0346–52, with the molecular gas mass ∼4× higher than the neutral atomic gas mass and ∼100× higher than the ionized gas mass.

    

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3. ALMA Reveals Extended Cool Gas and Hot Ionized Outflows in a Typical Star-forming Galaxy at Z = 7.13

   https://doi.org/10.3847/1538-4357/ac795b  

   Akins, Hollis B. ; Fujimoto, Seiji ; Finlator, Kristian ; Watson, Darach ; Knudsen, Kirsten K. ; Richard, Johan ; C. Bakx, Tom J. L. ; Hashimoto, Takuya ; Inoue, Akio K. ; Matsuo, Hiroshi ; et al ( July 2022 , The Astrophysical Journal)

   We present spatially resolved morphological properties of [CII] 158μm, [OIII] 88μm, dust, and rest-frame ultraviolet (UV) continuum emission for A1689-zD1, a strongly lensed, sub-L* galaxy atz= 7.13, by utilizing deep Atacama Large Millimeter/submillimeter Array (ALMA) and Hubble Space Telescope (HST) observations. While the [OIII] line and UV continuum are compact, the [CII] line is extended up to a radius ofr∼ 12 kpc. Using multi-band rest-frame far-infrared continuum data ranging from 52 to 400μm, we find an average dust temperature and emissivity index of$T_{\mathrm{dust}}={41}_{-14}^{+17}$K and$\beta ={1.7}_{-0.7}^{+1.1}$, respectively, across the galaxy. We find slight differences in the dust continuum profiles at different wavelengths, which may indicate that the dust temperature decreases with distance. We map the star formation rate (SFR) via IR and UV luminosities and determine a total SFR of 37 ± 1M_⊙yr⁻¹with an obscured fraction of 87%. While the [OIII] line is a good tracer of the SFR, the [CII] line shows deviation from the localL_[CII]-SFR relations in the outskirts of the galaxy. Finally, we observe a clear difference in the line profile between [CII] and [OIII], with significant residuals (∼5σ) in the [OIII] line spectrum after subtracting a single Gaussian model. This suggests a possible origin of the extended [CII] structure from the cooling of hot ionized outflows. The extended [CII] and high-velocity [OIII] emission may both contribute in part to the highL_[OIII]/L_[CII]ratios recently reported inz> 6 galaxies.

    

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4. Synthesis of Ni–TiO Nanocomposites as Enzyme–Less, Amperometric Sensors for the Electrooxidation of Glucose

   https://doi.org/10.1149/2754-2734/acd404  

   de los Rios, J. P. ; Galvan, Vicente ; Prakash, G. K. ( May 2023 , ECS Advances)

   The simple synthesis of a Ni–TiO₂nanocomposite supported on Vulcan carbon (XC–72 R) for the electrooxidation reaction of glucose is reported. Four transition metal weight ratios were synthesized and characterized. Cyclic voltammetry studies in 0.1 M NaOH demonstrate that the four metal catalysts can effectively oxidize 1 mM glucose, with the 3:1 (60%) Ni to Ti nanocomposite yielding the highest current. The 60% Ni–TiO₂/XC72R catalyst was used to construct an enzyme–less, chronoamperometric sensor for glucose detection in an alkaline medium. Using 50μM aliquots of glucose at a potential of +0.7 V (vs Hg/HgO), the sensor responded rapidly (<3 s), provided a sensitivity of 3300μA mM⁻¹cm⁻², detection limits of 144 nM (Signal/Noise = 3), and excellent selectivity and reproducibility. The glucose aliquot concentrations were then increased to 1 mM to mimic physiological blood conditions of 1–20 mM. At a potential of +0.7 V (vs Hg/HgO), the sensor continued to respond rapidly (<1 s), showed a sensitivity of 273.7μA mM⁻¹cm⁻², detection limits of 3.13μM (S/N = 3), and excellent selectivity and reproducibility. The catalyst also exhibited an ideal anti–poisoning capability to free chloride ions and negligible signals towards other interfering species.

    

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5. Two Massive, Compact, and Dust-obscured Candidate z ≃ 8 Galaxies Discovered by JWST

   https://doi.org/10.3847/1538-4357/acef21  

   Akins, Hollis_B ; Casey, Caitlin_M ; Allen, Natalie ; Bagley, Micaela_B ; Dickinson, Mark ; Finkelstein, Steven_L ; Franco, Maximilien ; Harish, Santosh ; Arrabal_Haro, Pablo ; Ilbert, Olivier ; et al ( October 2023 , The Astrophysical Journal)

   We present a search for extremely red, dust-obscured,z> 7 galaxies with JWST/NIRCam+MIRI imaging over the first 20 arcmin²of publicly available Cycle 1 data from the COSMOS-Web, CEERS, and PRIMER surveys. Based on their red color in F277W−F444W (∼2.5 mag) and detection in MIRI/F770W (∼25 mag), we identify two galaxies, COS-z8M1 and CEERS-z7M1, that have best-fit photometric redshifts of$z={8.4}_{-0.4}^{+0.3}$and${7.6}_{-0.1}^{+0.1}$, respectively. We perform spectral energy distribution fitting with a variety of codes (includingbagpipes,prospector,beagle, andcigale) and find a >95% probability that these indeed lie atz> 7. Both sources are compact (R_eff≲ 200 pc) and highly obscured (A_V∼ 1.5–2.5) and, at our best-fit redshift estimates, likely have strong [Oiii]+Hβemission contributing to their 4.4μm photometry. We estimate stellar masses of ∼10¹⁰M_⊙for both sources; by virtue of detection in MIRI at 7.7μm, these measurements are robust to the inclusion of bright emission lines, for example, from an active galactic nucleus. We identify a marginal (2.9σ) Atacama Large Millimeter/submillimeter Array detection at 2 mm within 0.″5 of COS-z8M1, which, if real, would suggest a remarkably high IR luminosity of ∼10¹²L_⊙. These two galaxies, if confirmed atz∼ 8, would be extreme in their stellar and dust masses and may be representative of a substantial population of highly dust-obscured galaxies at cosmic dawn.

    

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