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Wind-wave processes have generally been excluded from coupled Earth system models due to the high computational expense of spectral wave models, which resolve a frequency and direction spectrum of waves across space and time. Existing uniform-resolution wave modeling approaches used in Earth system models cannot appropriately represent wave climates from global to coastal ocean scales, largely because of tradeoffs between coastal resolution and computational costs. To resolve this challenge, we introduce a global unstructured mesh capability for the WAVEWATCH III (WW3) model that is suitable for coupling within the US Department of Energy's Energy Exascale Earth System Model (E3SM). The new unstructured WW3 global wave modeling approach can provide the accuracy of higher global resolutions in coastal areas at the relative cost of lower uniform global resolutions. This new capability enables simulation of waves at physically relevant scales as needed for coastal applications.

Background. We sought to determine the safety of treatment interruption (TI) and to identify parameters that would define patients with human immunodeficiency virus (HIV) for whom TI is safer. Methods. AIDS Clinical Trials Group 5170 was a multicenter, 96-week-long, prospective study of HIV-infected patients receiving antiretroviral therapy (ART) who had CD4⁺ cell counts >350 cells/mm³ and who underwent TI. Results. A total of 167 patients were enrolled. The median nadir in CD4⁺ cell count was 436 cells/mm³. The initial decrease (i.e., during the first 8 weeks) in CD4⁺ cell count after ART interruption was 20 cells/mm³/week; the subsequent decrease was 2.0 cells/mm³/week until week 96. Both the CD4⁺ cell count before enrollment and the increase in CD4⁺ cell count during ART predicted early decrease; later decrease was predicted by the level of interleukin7 at enrollment. A Centers for Disease Control and Prevention (CDC) diagnosis of a category B or C event was made for 2 and 2 patients, respectively (all had CD4⁺ cell counts >350 cells/mm³). At week 96, 17 patients had CD4⁺ cell counts ⩽250 cells/mm³, and 46 patients had resumed ART; 5 patients died (unrelated to HIV or acquired immunodeficiency syndrome). In a multivariate analysis, a higher nadir in CD4⁺ cell count (>400 cells/mm³), a lower HIV load (<50 copies/mL) at the time of TI, and an HIV load ⩽22,000 copies/mL before ART predicted a longer time to the primary end point (CDC category B or C event, death, CD4⁺ cell count ⩽250 cells/mm³, or resumption of ART). Conclusion. Disease progression after TI was low in this cohort. A higher nadir in CD4⁺ cell count, a lower HIV load before ART, and an HIV load ⩽50 copies/mL at the time of TI predicted a longer time to the primary end point.

A key component of the baryon cycle in galaxies is the depletion of metals from the gas to the dust phase in the neutral ISM. The METAL (Metal Evolution, Transport and Abundance in the Large Magellanic Cloud) program on the Hubble Space Telescope acquired UV spectra toward 32 sightlines in the half-solar metallicity LMC, from which we derive interstellar depletions (gas-phase fractions) of Mg, Si, Fe, Ni, S, Zn, Cr, and Cu. The depletions of different elements are tightly correlated, indicating a common origin. Hydrogen column density is the main driver for depletion variations. Correlations are weaker with volume density, probed by CI fine structure lines, and distance to the LMC center. The latter correlation results from an East-West variation of the gas-phase metallicity. Gas in the East, compressed side of the LMC encompassing 30 Doradus and the Southeast HI over-density is enriched by up to +0.3dex, while gas in the West side is metal-deficient by up to -0.5dex. Within the parameter space probed by METAL, no correlation with molecular fraction or radiation field intensity are found. We confirm the factor 3-4 increase in dust-to-metal and dust-to-gas ratios between the diffuse (logN(H)~20 cm-2) and molecular (logN(H)~22 cm-2) ISM observed from far-infrared, 21 cm, and CO observations. The variations of dust-to-metal and dust-to-gas ratios with column density have important implications for the sub-grid physics of chemical evolution, gas and dust mass estimates throughout cosmic times, and for the chemical enrichment of the Universe measured via spectroscopy of damped Lyman-alpha systems.