1/ Automobiles and Intake Fraction. Since cars are back in the news I thought I would retweet this model result I offered in early April 2020. I focused only on 1 micron particles & accounted for windows completely closed & cracked slightly open.

2/ Related air exchange rates were based on experimental results in literature for mid-sized sedans. Particle deposition to indoor surfaces were accounted for, as the surface to volume ratio in a 3 m3 cab is large. An important outcome was the intake fraction (IF)
3/ Here, IF is the number of particles (or virions in collective particles) inhaled by a receptor DIVIDED BY the number or particles (or virions in collective particles) emitted by an infector.
4/ Integrated over the two hour drive (in this example) the IF for all windows closed & a receptor at rest is 0.08 (8% of what comes out of the infectors respiratory system ends up in the respiratory system of the receptor). 8%! That is a very high intake factor.
5/ With additional ventilation from cracking a window open drops the IF to 0.012 (1.2%) still relatively high. Can get lower by opening more windows.
6/ An important point is that the intake fraction is not dependent on the amount emitted, and so the value is applicable to whatever the number of particles (or virions in particles) are being shed by an infector. Emission rate can be multiplied by IF to get at inhalation dose.
7/ In this analysis the IF ranges from approx 0.01 to 0.1. For a wide range of indoor spaces in buildings IF ranges from 0.0001 to 0.001. Intake fraction can be lowered w/ higher ventilation and/or better filtration (including portable HEPA filters), as well as UVGI for virions.
8/ Note that for large outdoor sources of pollution (think busy highways, power plants) with a receptor on the order of hundreds of meters to kilometers downwind the IF is typically on the order of 1 billionth to 1 trillionth.
9/ For the very special case of an inert pollutant (non-reactive and not removed by controls or surfaces) at steady-state IF = respiratory minute volume / volumetric flow of outdoor air through indoor space. IF = Qb/Qv
10/ I am working on a blog related to the use of intake fraction as a conceptual and quantitative tool for assessing indoor environments where exposure to SARS-CoV-2 may occur.
11/ Until then, I have posted some old handwritten course notes on intake fraction at https://t.co/iKuCeJKsrt

Apologies for sloppy writing. Enjoy the analogy of candles vs power plants in terms of inhalation of fine particles. Candles 👎. I know, different compositions.
12/ Also, if everyone in the vehicle wears masks the intake fraction is reduced on two fronts, less emissions from the infector and less inhalation of virus-laden particles by receptor. To be included in blog. Just do it!

More from Science

https://t.co/hXlo8qgkD0
Look like that they got a classical case of PCR Cross-Contamination.
They had 2 fabricated samples (SRX9714436 and SRX9714921) on the same PCR run. Alongside with Lung07. They did not perform metagenomic sequencing on the “feces” and they did not get


A positive oral or anal swab from anywhere in their sampling. Feces came from anus and if these were positive the anal swabs must also be positive. Clearly it got there after the NA have been extracted and were from the very low-level degraded RNA which were mutagenized from

The Taq.
https://t.co/yKXCgiT29w to see SRX9714921 and SRX9714436.
Human+Mouse in the positive SRA, human in both of them. Seeing human+mouse in identical proportions across 3 different sequencers (PRJNA573298, A22, SEX9714436) are pretty straight indication that the originals

Were already contaminated with Human and mouse from the very beginning, and that this contamination is due to dishonesty in the sample handling process which prescribe a spiking of samples in ACE2-HEK293T/A549, VERO E6 and Human lung xenograft mouse.

The “lineages” they claimed to have found aren’t mutational lineages at all—all the mutations they see on these sequences were unique to that specific sequence, and are the result of RNA degradation and from the Taq polymerase errors accumulated from the nested PCR process
JUST ONE PERSON—UK 🇬🇧 scientists think one immunocompromised person who cleared virus slowly & only partially wiped out an infection, leaving behind genetically-hardier viruses that rebound & learn how to survive better. That’s likely how #B117 started. 🧵 https://t.co/bMMjM8Hiuz


2) The leading hypothesis is that the new variant evolved within just one person, chronically infected with the virus for so long it was able to evolve into a new, more infectious form.

same thing happened in Boston in another immunocompromised person that was sick for 155 days.

3) What happened in Boston with one 45 year old man who was highly infectious for 155 days straight before he died... is exactly what scientists think happened in Kent, England that gave rise to #B117.


4) Doctors were shocked to find virus has evolved many different forms inside of this one immunocompromised man. 20 new mutations in one virus, akin to the #B117. This is possibly how #B1351 in South Africa 🇿🇦 and #P1 in Brazil 🇧🇷 also evolved.


5) “On its own, the appearance of a new variant in genomic databases doesn’t tell us much. “That’s just one genome amongst thousands every week. It wouldn’t necessarily stick out,” says Oliver Pybus, a professor of evolution and infectious disease at Oxford.

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MDZS is laden with buddhist references. As a South Asian person, and history buff, it is so interesting to see how Buddhism, which originated from India, migrated, flourished & changed in the context of China. Here's some research (🙏🏼 @starkjeon for CN insight + citations)

1. LWJ’s sword Bichen ‘is likely an abbreviation for the term 躲避红尘 (duǒ bì hóng chén), which can be translated as such: 躲避: shunning or hiding away from 红尘 (worldly affairs; which is a buddhist teaching.) (
https://t.co/zF65W3roJe) (abbrev. TWX)

2. Sandu (三 毒), Jiang Cheng’s sword, refers to the three poisons (triviṣa) in Buddhism; desire (kāma-taṇhā), delusion (bhava-taṇhā) and hatred (vibhava-taṇhā).

These 3 poisons represent the roots of craving (tanha) and are the cause of Dukkha (suffering, pain) and thus result in rebirth.

Interesting that MXTX used this name for one of the characters who suffers, arguably, the worst of these three emotions.

3. The Qian kun purse “乾坤袋 (qián kūn dài) – can be called “Heaven and Earth” Pouch. In Buddhism, Maitreya (मैत्रेय) owns this to store items. It was believed that there was a mythical space inside the bag that could absorb the world.” (TWX)