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Collective notation for guanosine tetraphosphate and pentaphosphate alarmones involved in the bacterial stringent response.
A nucleotide sugar carries an activated sugar linked to a nucleotide-containing group. It supports selective glycosyl transfer; donor identity alone does not specify the linkage or final glycan structure.
Replacement of a bound nucleotide by another. A changed exchange rate can alter a protein state without proving direct competition at the nucleotide-binding site.
Inosine is the ribonucleoside of hypoxanthine. Hydrolytic deamination of adenosine replaces its exocyclic amino group with a carbonyl oxygen while retaining its sugar attachment.
A brominated thymidine analogue incorporated during DNA synthesis. Substitution changes buoyant density, allowing copied strands to be distinguished from unsubstituted strands.
Thymidine conventionally means the nucleoside containing thymine and deoxyribose. Its phosphorylated derivatives supply thymidine nucleotides for DNA metabolism.
The sugar identity matters: ribothymidine contains ribose instead. Distinguishing base, nucleoside, and nucleotide prevents a change in phosphate content from being hidden by an imprecise name.
Nucleophilicity describes how readily a species forms a bond by donating an electron pair to a specified electrophile. It is a kinetic property, evaluated by relative reaction rates under stated conditions.
It differs from basicity, which concerns the thermodynamic tendency to accept a proton. A bulky base can be effective at removing a proton while reacting slowly at a crowded carbon center. Solvent, charge, polarizability, and steric effects all influence nucleophilicity, so there is no universal ranking valid for every electrophile and medium.
Two-dimensional nuclear Overhauser effect spectroscopy, detecting NMR cross-relaxation between nuclear spins.
Rotating-frame Overhauser effect spectroscopy, using NMR cross-relaxation during a spin-lock period.
Transfer of magnetization through a network of coupled spins, which can create indirect NOE correlations.
A material that supplies energy through a nuclear reaction, usually nuclear fission in a power nuclear reactor. Its usable performance depends on its thermal and mechanical response as well as its nuclear composition.
Permanent dimensional change accumulated over temperature cycles. anisotropic thermal expansion can create mismatch stresses in a polycrystalline material, but noncancelling irreversible accommodation is needed for net growth; a freely expanding, uniformly heated elastic single crystal returns to its original dimensions.
Irradiated nuclear fuel removed from a reactor. Residual actinides coexist with fission products and activation products; radioactivity and decay heat continue after shutdown.
A once-through fuel cycle in which spent nuclear fuel is managed without recovering its constituents for a further fuel irradiation.
Pinned article: Introduction to the OurBigBook Project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
Intro to OurBigBook
. Source. We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivativeVideo 2. OurBigBook Web topics demo. Source. - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension. 
- Infinitely deep tables of contents:
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact