Questions about JOS 3 development

[CeliaSondaz]

Hello,

Thanks a lot for your previous help.

As I mentioned in an e-mail, I want to use the JOS 3 model and for that I try to understand it. So, I have several questions about the construction of the model:

• The set point temperature is the "the body temperature of the model that does not have a thermoregulation system". What about the AVA blood flow in this passive model? Is Oava equal to 0.9126 as the equation (49) at the thermal equilibrium let it suppose or to 0? In the python code, it seems equal to 0 but I'm not sure to understand why?
• How did you choose the number of iterations for the initialization?
• I see some value differences between your article and the python code. Especially, the thermal capacity of the pelvis core is equal to 13.834 Wh/K in the python code and to 16.119kJ/K = 4.478Wh/K. Which value is correct ? How did you determine these capacity values?
• Same question for the conductance ms-fat in the pelvis : is it 0.3738 W/K or 10.37 W/K?
• The parameter "posture" have an effect on the convective and radiative coefficients. Does it take into account the contact with a chair for the sitting posture or with a bed or the floor for the lying posture?

Can you help me with that ?

Thank you very much again,

[TanabeLab]

Sorry for my late response. I have been quite busy so have not been able to follow up but will do this weekend.
Thank you!

Akihisa Nomoto

[CeliaSondaz]

Thanks a lot for your update. I'm looking forward to having your answers to my questions. It will be really useful for me and my PhD project.

Célia Sondaz

[CeliaSondaz]

Hello,
Sorry to bother you again. Do you have time to help me and to answer my questions?
Thank you for your help.
Célia Sondaz

[TanabeLab]

The value differences that you pointed out are currently under investigation. Please wait for a while. Sorry for this inconvenience...

[yoshito-takahashi]

Dear Celia Sondaz

I'm so sorry for the late reply.

• The set point temperature is the "the body temperature of the model that does not have a thermoregulation system". What about the AVA blood flow in this passive model? Is Oava equal to 0.9126 as the equation (49) at the thermal equilibrium let it suppose or to 0? In the python code, it seems equal to 0 but I'm not sure to understand why?

In this passive model, the AVA blood flow rate is set to 0. As you indicated, it is not 0 in thermo-neutral. I will think about validity of it in the future model.

• How did you choose the number of iterations for the initialization?

By confirming the parameters have become stable.

• I see some value differences between your article and the python code. Especially, the thermal capacity of the pelvis core is equal to 13.834 Wh/K in the python code and to 16.119kJ/K = 4.478Wh/K. Which value is correct ? How did you determine these capacity values?
• Same question for the conductance ms-fat in the pelvis : is it 0.3738 W/K or 10.37 W/K?

Thank you for finding my mistakes. I revised the code in ver.0.3.2.

• The parameter "posture" have an effect on the convective and radiative coefficients. Does it take into account the contact with a chair for the sitting posture or with a bed or the floor for the lying posture?

No it doesn't. The elder model had it. Adding the effect of the contact surface is a future work.

[CeliaSondaz]

Dear Yoshito,
Thank you very much for your answer, the checking and the version 0.3.2.
I'm really interested by the AVA issue, so please let me know if you have any update about it. I will probably do some research on this topic on my side. I will keep you posted.
Thanks a lot

[CeliaSondaz]

Dear Yoshito Takahashi,
I hope you're well.
Since my last message about the AVA question, I have worked on JOS 3 and I've tried to modify the initial AVA calculation. I've modified the line 370 and 371 of JOS 3.py.
I've changed the lines :

 if self.options["ava_zero"] and passive:
            bf_ava_hand = 0
            bf_ava_foot = 0

To :

if self.options["ava_zero"] and passive:
            bf_ava_hand, bf_ava_foot = threg.ava_bloodflow([0]*17, [0]*17,
            self._height, self._weight, self._bsa_equation, self._age, self._ci)

According to you, is it correct ?

Moreover, I find some differences between your article and the code so I have done some changes on the ava_bloodflow function in the thermoregulation module.
Before my changes :

cap_bcr = [10.2975, 9.3935, 13.834]
sig_ava_hand = 0.265 * (err_bcr + 0.43) + 0.953 * (err_msk + 0.1905) + 0.9126
sig_ava_foot = 0.265 * (err_bcr - 0.97) + 0.953 * (err_msk - 0.0095) + 0.9126

After my changes :

cap_bcr = [10.2975, 9.3935, 4.488]
sig_ava_hand = 0.265 * (err_msk + 0.43) + 0.953 * (err_bcr + 0.1905) + 0.9126
sig_ava_foot = 0.265 * (err_msk - 0.997) + 0.953 * (err_bcr + 0.0095) + 0.9126

Is it correct ?

After these modifications, the initial core temperatures seem low (TcrHead = 36.87°C TcrPelvis = 36.85°C). Is it normal or not ? If not, do you know what is my error ?

Thanks a lot for your help and for your model,

[suteacsute]

Has anyone got the answer? I agree with CeliaSondaz's suggestion. It seems that "err_bcr" and "err_msk" are reversed, and "0.97" is incorrect. In addition, if "cap_bcr" refers to the capacity ratio for weighting, then I think the values [37.071, 33.817, 16.119] should be transformed to [10.2975, 9.3935, 4.477].

Has the person responsible or the supervisor checked the content? Were the same codes used for the results in the paper of Energy & Buildings?

Is he an author in below?
https://jp.linkedin.com/in/yoshito-takahashi-b77312161

Another paper for JOS-3 mentions only 83 nodes (Plevis doesn't have muscle and fat).

[yoshito-takahashi]

Sorry for the late reply.
I have been very busy at work.

I fixed the function calculating AVA blood flow.
Could you check the branch jos3-dev-0.4.1 ?
Your modifications at line 370 and 371 is also correct, but I think these core temperature values are low, so, I leave them as original.

The same codes used for the paper are here.
https://github.com/TanabeLab/JOS-3/releases/tag/v0.3.1

It is correct that the nodes of JOS-3 have 85 nodes.
I'm sorry to have you confused.

[suteacsute]

Dear Yoshito Takahashi and Akihisa Nomoto,

I've noticed a potential issue in your paper.

In equations (40) and (41), you've used symbols "Â" and "Mnshiv"
which do not appear in the "Symbols" section of your paper.

I believe "Â" might be a garbled character, and "Mnshiv" might be intended to be "Mnst."
Could you kindly clarify and confirm this?

Additionally, it seems that "Mnst" is not utilized in the provided Python code.
for i, bn in enumerate(BODY_NAMES):
# If the segment has a muscle layer, muscle blood flow increases.
if not IDICT[bn]["muscle"] is None:
bf_ms[i] += (mwork[i] + mshiv[i])/1.163
# In other segments, core blood flow increase, instead of muscle blood flow.
else:
bf_cr[i] += (mwork[i] + mshiv[i])/1.163
return bf_cr, bf_ms, bf_fat

Thank you for your attention to this matter.
Sincerely,

[yoshito-takahashi]

Hi.
Thank you for pointing it out.
I will check it out.

Regards

(@AkihisaNomoto

[CeliaSondaz]

Dear Yoshito Takahashi and Akihisa Nomoto,

I am reaching out regarding another issue with JOS3 that I have encountered.

When simulating an increase in activity (as demonstrated in the provided code and figure), the core temperature initially decreases before rising again. This phenomenon seems to be connected to the increase in blood flow in the muscle: this issue does not occur delling the code lines pasted by suteascute.
Does this initial drop in temperature appear correct to you? If not, do you have any ideas on how to resolve this problem?

Thank you in advance for your consideration,

Best regards,

`import jos3
import pandas as pd
import matplotlib.pyplot as plt

model = jos3.JOS3(ex_output= "all" )

dt=60

model.To =20
model.RH = 40
model.Icl=0.1
model.PAR = 1/0.8
model.simulate(int(200*60/dt), dtime=dt)

model.PAR =9/0.8
model.simulate(int(30*60/dt), dtime=dt)

model.PAR =1/0.8
model.simulate(int(30*60/dt), dtime=dt)

d = model.dict_results()
df = pd.DataFrame(model.dict_results()) # Make pandas.
`

[yoshito-takahashi]

@suteacsute
Hi.
Sorry for the delay in replying. As you pointed out, the letters are garbled, and the character dot, meaning "multiply," is correct. It seems to have been converted during the proofreading stage.

Also, for the BF formula, it is difficult to answer it. This is because non-shivering thermogenesis does not involve activity and may not lead to an increase in blood flow. Since I cannot conclude this matter at this time, I leave the python code as it is. I added the comment about it in read.me.

Thank you very much for checking and pointing this out.