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The unparalleled global effort to combat the continuing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic over the last year has resulted in promising prophylactic measures. However, a need still exists for cheap, effective therapeutics and targeting multiple points in the viral life cycle could help tackle the current as well as future coronaviruses. Here we leverage our recently developed, ultra-large scale in silico screening platform, VirtualFlow, to search for inhibitors that target SARS-CoV-2. In this unprecedented structure-based virtual campaign, we screened roughly 1 billion molecules against each of 40 different target sites on 17 different potential viral and host targets. In addition to targeting the active sites of viral enzymes, we also targeted critical auxiliary sites such as functionally important protein-protein interactions., Graphical Abstract, Highlights • Ultra-large in silico screen of targets important for the replication of SARS-CoV-2 (85) • Screening of multiple functional sites on individual target proteins (70) • 17 target proteins, 45 screens, ∼50 billion docking instances to target SARS-CoV-2 (84) • Conservation in some target sites means hits could exhibit pan-coronavirus function (85)

Background: Contact with livestock wastewater on farms and in communities can pose a risk to human and animal health. Methods: This cross-sectional study was conducted in 180 households and 24 pig farms (96 wastewater samples) to explore information about pig production, livestock waste management, antibiotic use, and to analyze antibiotic residues and microbial contamination, respectively. Results: Of the 120 households raising pigs, biogas systems were the most commonly used to treat animal waste (70%), followed by compositing (19%), and the remaining respondents discharged waste directly into drains or ponds (11%). The majority of respondents (78%) used antibiotics to treat and prevent disease in pigs, but 32% of them did not know of any disadvantages of antibiotic abuse. ELISA assays were performed on half of the wastewater samples (n = 48), demonstrating that residues of flouroquinolones and sulfonamides were present in 6.3% (3/48) and 22.9% (11/48) of tested samples, respectively. The average residual level of sulfamethazine was 27.8 ug/l. Further, E. coli concentrations exceeding regulatory levels in Vietnam were found in nearly all samples. Salmonella spp. was also found in 57.3% of samples, though prevalence rates varied across the different sites. Finally, G. lamblia was found in 8.4% of samples, and C. parvum was found in 5.2% of samples. Conclusions: This study suggests that livestock wastewater carried potential harmful pathogens and antibiotic residues that could come into contact with humans in the community. Thus, appropriate operation and application of livestock wastewater treatment (such as biogas or composting) and management should be a continued focused.

The tutorial will review state-of-the-art optical access systems (GPON, GE-PON) from an operator perspective and then discuss evolution to next generation systems, especially extended reach systems, which enable benefits such as node consolidation.

Semiconductor optical amplifiers are used to simultaneously demonstrate reach and split extension of a commercial GPON system to the 128 ONT and 60km limits permitted in the GPON transport layer specification.