Does anyone know of a proof, that the divergence of a vector field exists?

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Why do individuals contract a different asbestos related disease when exposed to the same dose and same type?

Exposure to asbestos can result in asbestos related disease such as pleural plaques, pleural thickening, asbestosis, lung cancer and mesothelioma. Assuming a like for like exposure what factors...

09 February 2024 1,526 0 View

Is there a decommodification index calculated for each country in the world?

Esping-Andersen index measures the ability of the state to protect people from being part of "the market", and it is based on pension, sickness and unemployment protection. Few countries have...

29 October 2023 699 1 View

How do I add supplemental material from a published OA paper ?

20 September 2023 6,335 2 View

What differentiates 'energizing music' from up-tempo music in general?

Playlists of functionally-therapeutic music (FTM) for relaxing are in abundance. Where might one find studies focused on 'energizing' FTM recordings?

24 March 2023 6,462 0 View

How to Improve solar panel efficiency?

Buy one of the more efficient solar panel models Buy panels with High Concentrated Photovoltaic (CPV) Cell Avoid installing solar panels in shaded areas Get an expert to install your solar...

13 November 2022 8,391 4 View

Could anyone provide a summary, of what’s going on in these six papers on the holonomy group?

Recently I became aware of ‘The Holonomy Group’. This is to do with how the components of vectors alter, upon their parallel transport in a Riemann space. There are six papers on ‘The Holonomy...

24 August 2022 1,282 1 View

RNA manual method - Trizol (ThermoFisher) and RNAIso Plus (Takara) what is great with Trizol over RNAIso Plus?

I'm isolating RNA using RNAIso Plus (Takara). I need to know what is difference between Trizol and RNAIso Plus. Thanks in advance. Roger JCMR

19 July 2022 6,455 3 View

Suggest best research centers offering training in bisulfite conversion and epigenetics?

Centers in India that offer hands-on training in bisulfite conversion, DNA methylation, expression, and epigenetics are preferred.

24 May 2022 7,867 2 View

Do you have experience with the Maritime Automatic Identification System (AIS)?

I am a member of a FedTech Foundry team investigating AIS enhancements. Our team has developed a short survey (9 questions, estimated time to complete is less than 10...

07 May 2022 322 3 View

How do you create a multi-graph plot labeled for publication using multiclass ROC curves in R?

I'm using RStudio and I keep trying to use plot_grid to create my multiclass ROC graphs, but I keep getting the error: "cannot convert object of class roc to grob." Additionally, each of the...

19 February 2022 1,056 4 View

How to calculate CCS for Sodiated adduct ions and Multiply Charged Ions?

I'm currently working on calculating the collision cross section (CCS) for various ions, and I'm facing challenges when dealing with sodiated and multiply charged ions. Most of the resources I’ve...

08 August 2024 8,329 0 View

1. If I can quantize the atom using this hyperbolic spiral and classical physics, could nature do the same?

If we map as a continuous motion an ionising electron (beginning its journey at n=1) in an H atom, a specific hyperbolic spiral appears (see animation). When we solve this spiral formula, we find...

07 August 2024 5,343 2 View

How are iso-frequency contours plotted?

Let's say we have a standard, regular hexagonal honeycomb with a 3-arm primitive unit cell (something like the figure attached; the figure is only representative and not drawn to scale). The...

07 August 2024 1,937 1 View

Inquiry on Maximum Nucleic Acid Volume for 2.5 mL Liposome Solution?

I am currently working on a project involving liposomes and need to determine the maximum volume of siRNA that can be added to a 2.5 mL liposome solution with a total lipid concentration of 10...

30 July 2024 6,420 1 View

What is the best method to detect the chemical composition of pollen ?

I have multiple small samples of grass pollen with anthers. I want to find a method to identify concentrations of proteins, lipids, and other various elements for these samples. any suggestions?

28 July 2024 5,331 1 View

How can I use DFT-D3 correction ( Siesta version 5.0.1)?

Dear Siesta Users, I installed Siesta 5.0.1 and I want to use Grimme's D3 correction. According to the 5.0.1 manual, I could use a few parameters to include the D3 correction in the...

27 July 2024 5,748 0 View

EDC carbodiimide and NHS easter 's half life among different pH?

It has been long known that EDC carbodiimide and NHS easter's half life agains hydrolysis are highly related to pH. However, very surprisingly, not yet found a paper giving a table/chart of their...

25 July 2024 8,738 0 View

Is the zero-zero component of the metric tensor equal to 1 for accelerating reference frames?

Consider the case of negligible gravity but there is an accelerating reference frame. Its origin traces out a trajectory, or world line, seen in some inertial reference frame. The Lorentz metric...

24 July 2024 1,608 15 View

Mechanochemistry: ball to powder mass or ball to powder volume?

I run mechanochemical reactions that involves the use of a large amount of catalyst (1:1 molar ratio to the reactant). When I try to understand the effect of amount of catalyst on the reaction, I...

23 July 2024 9,938 1 View

How to eliminate the carry-over effect in GC-MS/MS system?

Hi, I am a PhD student working at Jagiellonian University, Faculty of Chemistry. My work is related to the development of new analytical methods for the quantification of short-chain fatty acids...

22 July 2024 5,492 6 View

William Mullin

You will find a thorough proof in the book "Div, Grad, Curl and All That" by H. M Schey, W. W. Norton

Jacques Lavau

There is at least an inferior horizon limiting the validity and competence of the scholar geometry we were taught. Unlimited extrapolation from our macroscopic habits into the microphysics domain has never been validated.