sradman
Joined 12 years ago
Joined 12 years ago
[1] https://www.cbc.ca/radio/quirks/homo-sapiens-braved-cold-mad...
There are a number of First-of-a-Kind SMR and Micro Reactors planned for the U.S., UK, and Canada. The advantage of the three leading lightwater SMRs (NuScale VOYGR, GE Hitachi BWRX-3000, and Rolls Royce SMR) are fast time to market due to the existing supply chain and continuous innovation on well understood technology. The problem is not so much the solid fuel, but the Zirconium clad fuel bundles that produce explosive hydrogen gas during Loss-of-Coolant-Accidents (LOCA). Accident Tolerant Fuels are being deployed now and may be another important innovation that reduces the likelihood of meltdowns but these systems also address the main sources of LOCAs: 1. isolation condenser system (ICS) replace pressure release valves that caused the Three Mile Island accident, and 2. passive coolant circulation systems that don't require external/backup power like the ones that failed during the Fukushima accident.
The problem with this class of lightwater SMR is that they are essentially base load power and the projected Nth-of-a-Kind costs will be competitive with fossil fuels (coal and natural gas) at best but are not cost competitive nor a good complement to intermittent renewables (wind and solar). They are a good slot-in replacement for existing coal fired plants.
There are also a number of Advanced SMRs and Micro Reactors (mobile and campus-size) that have announced First-of-a-Kind builds like the X-Energy Xe-100, TerraPower/GE Hitachi Natrium, ARC-100, Moltex SSR-W, USNC MMR, Xe-Mobile, and Westinghouse eVinci. These designs compete on a much larger landscape of theoretical trade-offs that may leapfrog the lightwater SMRs. I prefer this diverse mix of technologies and applications over a single anointed technology like Liquid fluoride thorium reactors (LFTRs). YMMV.
Simpson's Paradox is more of a data artifact that you have to be aware of. I didn't know about this statistical anomaly before but the takeaway is that if you see a effectiveness percentage decrease from 97% to 77% then you should also check that the value in each age cohort because each individual cohort may surprisingly be above 90%. The Israeli data might be fine but I want to see the "age corrected" range rather than a single effectiveness number.
The bottom line is that we will get good data moving forward from the Israeli 3rd dose program with other quality data sets soon to follow from the U.S., UK, Canada, Singapore, etc.
What we have not yet seen is any good evidence that the vaccinated are contributing to spread, though in the Fauci interview he indicated that the R(t) in the unvaccinated was non-zero. This is an important question, IMO.
[1] https://covid19-sciencetable.ca/ontario-dashboard/#riskbyvac...
The 3rd dose is safe and will probably provide a small benefit to the recipient as Shane Crotty described in TWiV 802 [5]. The downside is that these doses are in short supply globally where they could make a significant difference.
[1] https://www.covid-datascience.com/post/israeli-data-how-can-...
[2] https://en.wikipedia.org/wiki/Simpson%27s_paradox
[3] https://lemonadamedia.com/podcast/dr-fauci-answers-your-bigg...
[4] (YouTube ~3.5min @36m45s) https://youtu.be/93Rnjmr7iCk?t=36m45s
These are not fatal flaws, IMO, just gaps in need of attention.
I haven't checked recently, but I was unable to determine the type of ? parameters in SQLite prepared statements. Maybe this is something that can also be accommodated with STRICT tables.
> We present evidence for a previously unknown major extinction event in sharks that occurred in the early Miocene, ~19 million years ago. During this interval, sharks virtually disappeared from open-ocean sediments, declining in abundance by >90% and morphological diversity by >70%, an event from which they never recovered. This abrupt extinction occurred independently from any known global climate event and ~2 million to 5 million years before diversifications in the highly migratory, large-bodied predators that dominate pelagic ecosystems today, indicating that the early Miocene was a period of rapid, transformative change for open-ocean ecosystems.
> To investigate the importance of the spike polybasic CS of SARS-CoV-2 (PRRAR), a number of spike mutants predicted to modulate the efficiency of furin cleavage were generated (Fig. 1a), including: substituting two upstream arginines to produce a monobasic CS similar to SARS-CoV spike (monoCS), replacing the tribasic CS with the furin CS of a highly pathogenic H5N1 avian influenza haemagglutinin containing seven basic amino acids (H5CS) and two naturally occurring deletions seen following passage in Vero E6 cells and/or in clinical isolates21,26. The first deletion removes eight amino acids including all three arginines of the PRRAR site (ΔCS), while the other removes five flanking amino acids but retains the tribasic CS (Δflank). The mutations were engineered into a spike expression plasmid to enable cell surface expression and generation of coronavirus lentiviral PVs. In addition, to study the importance of the PRRAR motif in the context of live virus, we used a naturally occurring Vero-cell-adapted mutant SARS-CoV-2, ΔCS26. This variant and the wild-type (WT) virus from which it was derived were cloned by limiting dilution to enable studies using individual genotypes.
This is the horror of in vitro and in vivo viral lab research and the result is a magnificent advancement of our understanding of SARS-CoV-2, the furin cleavage site, and its role in TMPRSS2 assisted membrane entry. This research follows the equally eye-opening paper covered in TWiV 715 that explained why hydroxychloroquine (HCQ) failed; Vero E6 cells lack TMPRRS2 so HCQ fully blocks entry via endocytosis. It should be noted that this study includes MERS-CoV which also has a furin cleavage site; falsifying one of the claims of Wade's article.
Regardless, lab experiments begin with one or more viral isolates and molecular clock techniques should show that the original Wuhan variant has almost identical non-coding genome segments compared to existing lab isolates. The RaTG13 sequence is a very distant relative using this measure. Also, RaTG13 is not an isolate, only an RNA sample collected in wild bat anal swabs. Conflating viral isolates with RNA samples seems to be a common error; an entry in a genetic database does not imply that a viable viral line exists in a lab. A RaTG13 lab isolate would have been an important achievement to further our scientific understanding.
I'm confused by the dismissals of the natural origins hypothesis. The horseshoe bat roosts, that are studied, are mostly found in or near Kunming, Yunnan. This lush wild area is part of the Lancang/Mekong River watershed/ecosystem shared by nocturnal bats and nocturnal arboreal mammals like palm civets, pangolins, and raccoon dogs. The nearby villages contain people engaged in guano collection, the wildlife trade, and domestic livestock farming.
The average incubation time of COVID-19 is 4.5 days. Armed with Google maps and a basic understanding of planes, trains, and automobiles we can gauge travel time from Kunming Airport to either Wuhan Tianhe International Airport (2 hr 5 min) or Guangzhou Baiyun International Airport (2 hrs). In 2003, SARS-1 emerged in Guangzhou (near Hong Kong) and the now demonized Dr. Zheng-li Shi and her team traced the origins to palm civets (the intermediate host). Why is this so hard? Why do we not ridicule the assumption that travel between major Chinese transportation hubs must leave a wake of infections along the path?
Finally, Wade's article mentions a U.S. State Department claim [2]:
> The U.S. government has reason to believe that several researchers inside the WIV became sick in autumn 2019, before the first identified case of the outbreak, with symptoms consistent with both COVID-19 and common seasonal illnesses.
If true, this is an important early super-spreader event but the remainder of the release consists of a facile analysis performed by people more knowledgeable in geopolitics than science.
[1] https://www.nature.com/articles/s41564-021-00908-w
[2] https://2017-2021.state.gov/fact-sheet-activity-at-the-wuhan...