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Are the social-distancing measures implemented against SARS-CoV-2 also suppressing the spread of other viruses?

Yes, this helps as well with other infectious diseases. A good example is the flu, which season was measurably shorter this year than in other years on record. See the figure from the reference 1 for ...
Chris's user avatar
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41 votes

Are the social-distancing measures implemented against SARS-CoV-2 also suppressing the spread of other viruses?

In addition to Chris' answer above, the effect is even more pronounced in Southern Hemisphere countries where flu season started during the pandemic. The New Zealand lockdown and health response ...
Aethernaught's user avatar
37 votes

Why don't viruses reach broad concentration outdoors in a city like allergens?

2, 4, 5, and 6. 6 being that the UV light (from the sun), fluctuations in temperature, humidity, wind etc mean that the virions are decayed relatively rapidly for most virus species. To address (1): ...
bob1's user avatar
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25 votes
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Is there a bacterium that became a virus?

This virology site has a post about a 2017 paper about membrane-vesicled plasmids that act in ways that are theorized to be precursors to how viruses work: It is likely that the plasmid-containing ...
Alex Reynolds's user avatar
22 votes

Why don't viruses reach broad concentration outdoors in a city like allergens?

In another answer elsewhere on StackExchange, a poster estimated that there might be something like 100 g to 1 kg of SARS-CoV-2 virus worldwide, and that's an estimate of all the virus, including what ...
Bryan Krause's user avatar
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17 votes

How do you calculate the time until the steady-state of a drug?

Here's a short simulation that show the process. You can find more about how to simulate a half decay process here You can notice that the first dose of 40 mg should decay to 20 mg in 30 hours, but ...
heracho's user avatar
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15 votes
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Examples of Differential equations in Biology

For biochemistry students the obvious link to differential equations is the Michaelis–Menten equation which is a simple model of the kinetics of reactions involving enzymes. Your students will be ...
Charles E. Grant's user avatar
14 votes

Is there a bacterium that became a virus?

There are giant viruses that some people think could be degenerate bacteria. https://en.wikipedia.org/wiki/Mimivirus Mimivirus shows many characteristics which place it at the boundary between ...
Willk's user avatar
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13 votes

Examples of Differential equations in Biology

Update please follow Charles E. Grant's advice and do Michaelis-Menten! Hodgkin-Huxley as suggested by commenter ctwardy is a great idea too. Original answer I would strongly recommend the book ...
Maximilian Press's user avatar
11 votes

How do you calculate the time until the steady-state of a drug?

heracho's answer does a good job showing the realistic timing. However you can do a pretty good approximation with a simple differential equation, where you approximate the daily dose as a continuous ...
thegreatemu's user avatar
8 votes

Empirical evidence for Group Selection?

Let's start with your definition. "Selection for traits that would be beneficial to a population of units at the expense of an individual unit possessing the trait" This is not a good definition of ...
Michael Andrew Bentley's user avatar
8 votes

Can we use differential equations for population that is discrete?

You can make the continuous approximation when the population size is large. As mentioned by arboviral, there are algorithms that allow you to perform stochastic simulations with discrete variables. ...
WYSIWYG's user avatar
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8 votes

How do you calculate the time until the steady-state of a drug?

Let's take a moment to think about what it means for a drug dosed multiple times to reach "steady-state": "steady-state" would mean that it doesn't matter much if you've been ...
Bryan Krause's user avatar
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7 votes

Exponential growth equation and bacteria

Considering your assumption: I'm just looking at the exponential part, where the simple exponential equation works. If we assume there's sufficient nutrients for bacteria to grow unchecked for ...
WYSIWYG's user avatar
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7 votes
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Isn't sexy son hypothesis circular?

The process is self-reinforcing but the argument is not circular (no tautology implied). As soon as some male traits are considered more sexy than others, then there is selection for females to like ...
Remi.b's user avatar
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7 votes
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Understanding expected mean number of breeding seasons

It's just a continuous version of the discrete calculation. The discrete version is the (infinite series) sum $$ \sum_{i = 0}^\infty S^i \cdot bp $$ adding up every (chance of survival to season $i$) ...
Armand's user avatar
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7 votes

Understanding expected mean number of breeding seasons

I think your explanation is correct. The expected value of the exponential distribution is: $$t \sim \text{e}^{-\lambda t} \implies \langle t \rangle = \int_0^\infty t \ \text{e}^{-\lambda t} \; \text{...
Domen's user avatar
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6 votes
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The title et al

The Latin phrase et alia (abbreviated et al.) means and others. It is not limited to biologists, nor those of different nationalities. If I refer to this computer graphics article, I can refer to it ...
Matthew Woo's user avatar
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Why is the null hypothesis of trait evolution Brownian motion?

I think that the simple answer to this question is that the present comparative methodology was largely established by Felsenstein 1985, American Naturalist. For mathematical convenience, he suggested ...
Maximilian Press's user avatar
6 votes

What does it mean to quantitatively describe a cell?

Quantitative in the context of biology is similar to chemistry, and means "how much of something there is" - for example, how much of a particular protein is produced under what conditions. ...
bob1's user avatar
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6 votes

Examples of Differential equations in Biology

Are Twelve ODEs for mitochondrial membrane potential (ΔΨm), and matrix concentrations of Ca2+, NADH, ADP, and TCA cycle intermediates, used to model the response of mitochondria to changes in ...
user21820's user avatar
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5 votes
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How can I obtain a computer readable model of Dr. Gerhard Michal's biological pathways map?

Roche's Biochemical Pathways works as a big png image and just put labels on the map. But you could try to extract data using queries like http://biochemical-pathways.com/pol/fts/query?query=Glutarate ...
Maxim Kuleshov's user avatar
5 votes
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Is "A" inhibiting "B" and vice-versa, a positive feedback loop?

The situation that you presented in which an entity A inhibits the production of another entity B which in turn inhibits A, is a positive feedback. In a network path or a loop the overall sign of the ...
WYSIWYG's user avatar
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5 votes
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Biological meaning of Lotka-Volterra Jacobian matrices

The Jacobian tells how the system changes along different state variables (which can be, for instance, the concentrations of the predator and the prey). The Jacobian matrix by itself doesn't give you ...
WYSIWYG's user avatar
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5 votes

Can we use differential equations for population that is discrete?

I'd hardly call myself an expert on this topic by any stretch of the imagination, but you can actually come up with good approximations based on ODE-based models by rounding off to the nearest whole ...
EJoshuaS - Stand with Ukraine's user avatar
5 votes
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Mathematical model about the relationship between two animal species

The model you present here is a special case of the Lotka-Volterra competition equations, where the two species have the same effect on each other (i.e., symmetric competition). Some things to think ...
Ben Bolker's user avatar
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5 votes
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Are resonances the reason receptors work?

Photoreceptors themselves dont act as oscilators, a single receptor is either 'on' or 'off' - it does not respond differently to different wavelenghts. Humans have Trichromatic vision, which means ...
Nicolai's user avatar
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5 votes

A cure for radiation exposure?

Would that be a good thing? Recent research from the Samson lab at MIT suggests that there are side effects from amplifying the DNA repair mechanism. Hyperactivity of a base-excision repair (BER) ...
Alex Reynolds's user avatar
5 votes

Remarkable attempts of studying biological systems axiomatically

It's hard for me to know the degree to which the Kaczynski quote is wrapped up in what you are interested in, so I will answer your question very narrowly without considering that quote: does there ...
Maximilian Press's user avatar
5 votes
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What could be a refuge in host-parasitoid models

The most typical situation is a size refuge, i.e. prey/hosts that are too large or too small to attack (or possibly too small to be useful) are not attacked, or are attacked less, than hosts that are ...
Ben Bolker's user avatar
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