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Terry Hsieh,1 Bradley S Gundlach,2 Sahar Ashrafzadeh,2 David Sarraf,3,4 Irena Tsui3,5,6 1Stein Eye Institute, University of California, Los Angeles, CA, USA; 2David Geffen School of Medicine, University of California, Los Angeles, CA, USA; 3Ophthalmology Department, West Los Angeles Veterans Health Administration, Los Angeles, CA, USA; 4Retinal Disorders and Ophthalmic Genetics - Stein Eye Institute, University of California, Los Angeles, CA, USA; 5Retina Division - Stein Eye Institute, University of California, Los Angeles, CA, USA; 6Doheny Eye Institute, University of California, Los Angeles, CA, USACorrespondence: Irena Tsui, Ophthalmology Department, West Los Angeles Veterans Health Administration, Los Angeles, CA, USA, Tel +1 310 825 7290, Fax +1 310 825 9946, Email itsui@jsei.ucla.eduPurpose: To examine the return of patients to intravitreal injection clinic after the COVID-19 lockdown.Patients and Methods: The electronic medical records of all patients who received intravitreal injections at a tertiary care Veterans Health Administration (VHA) clinic 14 weeks post-lockdown (5/9/20-8/13/20) in Los Angeles County were reviewed. Reference groups included injection patients during the 7-week COVID-19 lockdown (3/19/20-5/8/20) and a 7-week pre-pandemic period in 2019 (3/19/19-5/8/19). Clinic volume was compared using a one-way ANOVA. Demographic data, medical and psychiatric co-morbidities, injection diagnoses, visual acuities, and clinic volumes were compared between the 3 periods using a generalized estimating equation multivariate analysis.Results: The post-lockdown period group averaged 25.1 visits per week, compared with 12.3/week during lockdown and 25.4/week pre-COVID in intravitreal injection clinic. In the post-lockdown period, the VHA injection clinic returned closer to the pre-lockdown volume compared to the VHA comprehensive clinic (98.9% vs 57.4%, p < 0.001). Post-lockdown, COPD patients and organ transplant patients were less likely to receive injections compared to 2019 (OR 0.76 p = 0.008, OR 1.37 p < 0.0001, respectively). Patients with a diagnosis of cancer increased in proportion between the pre-pandemic and the post-lockdown periods (OR 1.31, p = 0.007). No differences were found, according to psychiatric co-morbidities. After lockdown, the proportion of patients receiving injections for diabetic macular edema (DME) increased (OR 1.11, p = 0.01).Conclusion: Injection volume returned to pre-pandemic levels immediately after lockdown ended. However, patients with high-risk comorbidities did not return to intravitreal injection clinic post-lockdown. These results can inform medical organizations, which groups may need increased safety measures and targeted outreach to address their ophthalmic needs.Keywords: age-related macular degeneration, anti-vascular endothelial growth factor, coronavirus, co-morbidities, diabetic retinopathy, retina

About 10% of the energy usage on a typical university campus is spent to meetInformation Technology (IT) demands such as powering desktops, severs, printers, laptops, andother peripheral equipment. At UC Davis, the annual energy expenditure on IT alone wasapproximately $3 million (~$1.3 million excluding servers and related usage) in 2008. Thistranslates to nearly 12,800 equivalent tons of CO2 per year. In light of California’s greenhousegas reduction goals such as AB 32, UC campuses are crafting detailed plans to reduce energywaste and improve efficiency across all domains; IT efficiency is recognized as an importantarea of focus. It is well documented that IT energy use can be significantly reduced throughenergy efficiency measures and best practices. However, these strategies when implementedhave not been as successful as expected because they have not incorporated behavioral change,thereby missing the opportunity to maximize energy savings. Inherent principal-agent conflictsimpede behavior change, notably in the form of consumers on campus not paying the electricalbill for their IT energy use.The objective of the current work is to establish the PA problem with IT usage in auniversity setting and quantify the maximum potential savings possible by eliminating thisbehavioral component. Preliminary estimates have shown that the PA problem in computingamounts to $460,000 annually. It was found that lack of 1) incentives or policies, 2)collaboration amongst various stake holders and 3) awareness were some of the key barriers thatneed to be addressed to achieve any significant savings.

About 10% of the energy usage on a typical university campus is spent to meetInformation Technology (IT) demands such as powering desktops, severs, printers, laptops, andother peripheral equipment. At UC Davis, the annual energy expenditure on IT alone wasapproximately $3 million (~$1.3 million excluding servers and related usage) in 2008. Thistranslates to nearly 12,800 equivalent tons of CO2 per year. In light of California’s greenhousegas reduction goals such as AB 32, UC campuses are crafting detailed plans to reduce energywaste and improve efficiency across all domains; IT efficiency is recognized as an importantarea of focus. It is well documented that IT energy use can be significantly reduced throughenergy efficiency measures and best practices. However, these strategies when implementedhave not been as successful as expected because they have not incorporated behavioral change,thereby missing the opportunity to maximize energy savings. Inherent principal-agent conflictsimpede behavior change, notably in the form of consumers on campus not paying the electricalbill for their IT energy use.The objective of the current work is to establish the PA problem with IT usage in auniversity setting and quantify the maximum potential savings possible by eliminating thisbehavioral component. Preliminary estimates have shown that the PA problem in computingamounts to $460,000 annually. It was found that lack of 1) incentives or policies, 2)collaboration amongst various stake holders and 3) awareness were some of the key barriers thatneed to be addressed to achieve any significant savings.

Context. To understand how planets form in protoplanetary disks, it is necessary to characterize their gas and dust distribution and masses. This requires a combination of high-resolution dust continuum and molecular line interferometric observations, coupled with advanced theoretical models of protoplanetary disk physics, chemical composition, and radiative transfer. Aims. We aim to constrain the gas density and temperature distributions as well as gas masses in several T Tauri protoplanetary disks located in Taurus. We use the 12CO, 13CO, and C18O (2–1) isotopologue emission observed at 0.9″ with the IRAM NOrthern Extended Millimeter Array (NOEMA) as part of the MPG-IRAM Observatory Program PRODIGE (PROtostars and DIsks: Global Evolution PIs: P. Caselli & Th. Henning). Our sample consists of Class II disks with no evidence of strong radial substructures. We use these data to constrain the thermal and chemical structure of these disks through theoretical models for gas emission. Methods. To fit the combined optically thick and thin CO line data in Fourier space, we developed the DiskCheF code, which includes the parameterized disk physical structure, machine-learning (ML) accelerated chemistry, and the RADMC-3D line radiative transfer module. A key novelty of DiskCheF is the fast and feasible ML-based chemistry trained on the extended grid of the disk physical-chemical models precomputed with the ANDES2 code. This ML approach allows complex chemical kinetics models to be included in a time-consuming disk fitting without the need to run a chemical code. Results. We present a novel approach to incorporate chemistry into disk modeling without the need to explicitly calculate a chemical network every time. Using this new disk modeling tool, we successfully fit the 12CO, 13CO, and C18O (2-1) data from the CI, CY, DL, DM, DN, and IQ Tau disks. The combination of optically thin and optically thick CO lines allows us to simultaneously constrain the disk temperature and mass distribution, and derive the CO-based gas masses. The best-fit disk gas masses range between 0.005 and 0.04 M⊙. These values are in reasonable agreement with the disk dust masses rescaled by a factor of 100 as well as with other indirect gas measurements via, for example, modeling of the wavelength dependence of the dust continuum emission radii, and HD and CO isotopologue emission. [ABSTRACT FROM AUTHOR]

Context. The physics and chemistry of planet-forming disks are far from being fully understood. To make further progress, both broad line surveys and observations of individual tracers in a statistically significant number of disks are required. Aims. Our aim is to perform a line survey of eight planet-forming Class II disks in Taurus with the IRAM NOrthern Extended Millimeter Array (NOEMA), as a part of the MPG-IRAM Observatory Program PRODIGE (PROtostars and DIsks: Global Evolution; PIs: P. Caselli and Th. Henning). Methods. Compact and extended disks around T Tauri stars CI, CY, DG, DL, DM, DN, IQ Tau, and UZ Tau E are observed in ~80 lines from > 20 C-, O,- N-, and S-bearing species. The observations in four spectral settings at 210–280 GHz with a 1σ rms sensitivity of ~8–12 mJy beam−1 at a 0.9″ and 0.3 km s−1 resolution will be completed in 2024. The uv visibilities are fitted with the DiskFit model to obtain key stellar and disk properties. Results. In this first paper, the combined 12CO, 13CO, and C18O J = 2–1 data are presented. We find that the CO fluxes and disk masses inferred from dust continuum tentatively correlate with the CO emission sizes. We constrained dynamical stellar masses, geometries, temperatures, the CO column densities, and gas masses for each disk. The best-fit temperatures at 100 au are ~ 17–37 K, and decrease radially with the power-law exponent q ~ 0.05–0.76. The inferred CO column densities decrease radially with the power-law exponent p ~ 0.2–3.1. The gas masses estimated from 13CO (2–1) are ~0.001–0.2 M⊙. Conclusions. Using NOEMA, we confirm the presence of temperature gradients in our disk sample. The best-fit CO column densities point to severe CO freeze-out in these disks. The DL Tau disk is an outlier, and has either stronger CO depletion or lower gas mass than the rest of the sample. The CO isotopologue ratios are roughly consistent with the observed values in disks and the low-mass star-forming regions. The high 13CO/C18O ratio of ~23 in DM Tau could be indicative of strong selective photodissociation of C18O in this disk. [ABSTRACT FROM AUTHOR]