User talk:Rudolf.hellmuth

hard tissue
Curious to see if you could find any sources precisely defining what hard tissue is. I remain sceptical that nails.and hair are considered hard tissue. Kind regards Matthew Ferguson (talk) 21:41, 26 October 2015 (UTC)


 * It is saying that hard tissue has mineralised material. Soft tissues are collagen fibres with embedded cells. Cartilage is pretty soft. It is like rubber full of water. I wouldn't consider hair and nails as tissues because they don't have mineralised materials. They are biologically produced polymers.
 * In a review paper about soft tissues, Humphrey wrote about cartilage, but not bones. --Rudolf Hellmuth (talk) 22:50, 26 October 2015 (UTC)

Humphrey, J. D. (2003). Review Paper: Continuum biomechanics of soft biological tissues. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, 459(2029), 3–46. doi:10.1098/rspa.2002.1060

The dictionary definition source that is currently in the article states cartilage is a hard tissue. This source could be wrong of course but it would be good to provide better sources for this article. Matthew Ferguson (talk) 21:57, 26 October 2015 (UTC)


 * Dictionaries are not reliable sources of scientific jargons. --Rudolf Hellmuth (talk) 22:50, 26 October 2015 (UTC)


 * I guess there are two possible definitions of hard tissues. First, the mineralization, which includes enamel, the structural material of sea sponges, shells, etc. Second, in the mechanical response of the material. In this case, hard tissues would be linear elastic with a brittle failure mode, whereas soft tissues be non-linear elastic with damage occurring along considerable stretch ratios. --Rudolf Hellmuth (talk) 22:50, 26 October 2015 (UTC)

ArbCom elections are now open!
Hi, You appear to be eligible to vote in the current Arbitration Committee election. The Arbitration Committee is the panel of editors responsible for conducting the Wikipedia arbitration process. It has the authority to enact binding solutions for disputes between editors, primarily related to serious behavioural issues that the community has been unable to resolve. This includes the ability to impose site bans, topic bans, editing restrictions, and other measures needed to maintain our editing environment. The arbitration policy describes the Committee's roles and responsibilities in greater detail. If you wish to participate, you are welcome to review the candidates' statements and submit your choices on the voting page. For the Election committee, MediaWiki message delivery (talk) 13:55, 24 November 2015 (UTC)

Disambiguation link notification for April 7
Hi. Thank you for your recent edits. Wikipedia appreciates your help. We noticed though that when you edited Rui Barbosa, you added a link pointing to the disambiguation page Brazilian. Such links are almost always unintended, since a disambiguation page is merely a list of "Did you mean..." article titles. Read the FAQ* Join us at the DPL WikiProject.

It's OK to remove this message. Also, to stop receiving these messages, follow these opt-out instructions. Thanks, DPL bot (talk) 11:32, 7 April 2016 (UTC)

Bug in Petersen Matrix example?
Hi,

I think the page for the Petersen matrix contains a bug in the example. As far as I can see, the reaction equations are not consistent with the ODE and the matrix.

The 3rd reaction appears to be "ES -> E + P", hence, enzyme E is recovered. This is, however, neither reflected by the ODE (right hand side of dE/dt) nor by the stoichiometry matrix (coefficient for process 4 and and variable E is zero).

This can be resolved in two ways but I don't know which one is correct. Either the reaction equations is changed into "ES -> P" or the ODE and matrix need to be adapted for recovery of E. Note that in the version from 13:30, 25 September 2012‎, the matrix was still consistent with the given reaction equations (coefficient for process 4 and and variable E was unity).

Dkneis (talk) 08:27, 30 June 2016 (UTC)


 * You're right. The enzyme is recovered. I am going to fix the article, but you could do it yourself as well. Thanks! --Rudolf Hellmuth (talk) 22:59, 2 July 2016 (UTC)