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Hudson, André O (Ed.)This study reports the whole-genome sequence ofAchromobactersp. strain PD1, isolated from a wastewater treatment bioreactor. Using Illumina and Nanopore sequencing, a complete genome of 6,994,232 bp was obtained. This genome contains genes predicted to encode a complete pathway for cyanophycin synthesis, a candidate for nitrogen recovery from wastewater.more » « less
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The attached-eddy model (AEM) predicts that the mean streamwise velocity and streamwise velocity variance profiles follow a logarithmic shape, while the vertical velocity variance remains invariant with height in the overlap region of high Reynolds number wall-bounded turbulent flows. Moreover, the AEM coefficients are presumed to attain asymptotically constant values at very high Reynolds numbers. Here, the AEM predictions are examined using sonic anemometer measurements in the near-neutral atmospheric surface layer, with a focus on the logarithmic behaviour of the streamwise velocity variance. Utilizing an extensive 210-day dataset collected from a 62 m meteorological tower located in the Eastern Snake River Plain, Idaho, USA, the inertial sublayer is first identified by analysing the measured momentum flux and mean velocity profiles. The logarithmic behaviour of the streamwise velocity variance and the associated ‘$$-1$$’ scaling of the streamwise velocity energy spectra are then investigated. The findings indicate that the Townsend–Perry coefficient ($$A_1$$) is influenced by mild non-stationarity that manifests itself as a Reynolds number dependence. After excluding non-stationary runs, and requiring the bulk Reynolds number defined using the atmospheric boundary layer height to be larger than$$4 \times 10^{7}$$, the inferred$$A_1$$converges to values ranging between 1 and 1.25, consistent with laboratory experiments. Furthermore, nine benchmark cases selected through a restrictive quality control reveal a close relation between the ‘$$-1$$’ scaling in the streamwise velocity energy spectrum and the logarithmic behaviour of streamwise velocity variance. However, additional data are required to determine whether the plateau value of the pre-multiplied streamwise velocity energy spectrum is identical to$$A_1$$.more » « less
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Abstract We present high-resolution WIYN/NEID echelle spectroscopy (R ≈ 70,000) of the supernova (SN) 2023ixf in M101, obtained 1.51 to 18.51 days after explosion over nine epochs. Daily monitoring for the first 4 days after explosion shows narrow emission features (≤200 km s−1), exhibiting predominantly blueshifted velocities that rapidly weaken, broaden, and vanish in a manner consistent with radiative acceleration and the SN shock eventually overrunning or enveloping the full extent of the dense circumstellar medium (CSM). The most rapid evolution is in the Heiemission, which is visible on day 1.51 but disappears by day 2.62. We measure the maximum pre-SN speed of Heito be 25 km s−1, where the error is attributable to the uncertainty in how much the Heihad already been radiatively accelerated and to measurement of the emission-line profile. The radiative acceleration of CSM is likely driven by the shock–CSM interaction, and the CSM is accelerated to ≥200 km s−1before being completely swept up by the SN shock to ∼2000 km s−1. We compare the observed spectra with spherically symmetric r1w6bHERACLES/CMFGENmodel spectra and find the line evolution to generally be consistent with radiative acceleration, optical depth effects, and evolving ionization state. The progenitor of SN 2023ixf underwent an enhanced mass-loss phase ≳4 yr prior to core collapse, creating a dense, asymmetric CSM region extending out to approximatelyrCSM = 3.7 × 1014(vshock/9500 km s−1) cm.more » « less
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Urban surface and near-surface air temperatures are known to be often higher than their rural counterparts, a phenomenon now labeled as the urban heat island effect. However, whether the elevated urban temperatures are more persistent than rural temperatures at timescales commensurate to heat waves has not been addressed despite its importance for human health. Combining numerical simulations by a global climate model with a surface energy balance theory, it is demonstrated here that urban surface and near-surface air temperatures are significantly more persistent than their rural counterparts in cities dominated by impervious materials with large thermal inertia. Further use of these materials will result in even stronger urban temperature persistence, especially for tropical cities. The present findings help pinpoint mitigation strategies that can simultaneously ameliorate the larger magnitude and stronger persistence of urban temperatures.more » « less
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