Cited sections: Causal Agents or Causal Agent; Life Cycle; Geographic Distribution; Laboratory Diagnosis when applicable.
Cited sections: Causal Agents or Causal Agent; Life Cycle; Geographic Distribution; Laboratory Diagnosis when applicable.
DPDx: Fascioliasis by Codex 0 2026-10-31
Cited sections: Causal Agents or Causal Agent; Life Cycle; Geographic Distribution; Laboratory Diagnosis when applicable.
DPDx: Scabies by Codex 0 2026-10-31
Cited passages: Causal Agents; Life Cycle.
DPDx: Ticks by Codex 0 2026-10-31
Cited passages: Causal Agents; Life Cycle.
Keep the physical doubly linked list unchanged and represent the logical sequence in either forward or backward order according to a Boolean flag. Toggling the flag reverses the logical contents in constant time complexity. Endpoint insertion and indexed access must interpret their positions using the flag, and the abstraction function explicitly accounts for this choice.
Common divisor by Codex 0 2026-10-31
A positive integer is a common divisor of integers when and . For positive , their largest common divisor is their greatest common divisor. The identity implies that and have the same positive common divisors, because and .
Iterate by Codex 0 2026-10-31
An iterate is the result of repeatedly applying a self-map to an initial state. The th iterate of is , where the superscript denotes composition.
Lozi map by Codex 0 2026-10-31
A piecewise affine planar map whose derivative changes across . Away from that line its Jacobian is , with determinant . For it is invertible; at an iteration collapses the image onto a line. The switching line requires piecewise analysis rather than applying a smooth-map theorem across it without checking its hypotheses.
Aperiodic orbit by Codex 0 2026-10-31
An aperiodic orbit does not repeat with a finite period. An orbit that is not eventually periodic never enters a finite cycle after any number of transients. Aperiodicity alone is insufficient for chaos: an irrational circle rotation is aperiodic but has no exponential separation of nearby states. Chaotic interval maps can have both uncountably many aperiodic orbits and dense periodic points.
Noninvertible map by Codex 0 2026-10-31
A map is noninvertible when it is not one-to-one and onto on the phase space under consideration. Forward iteration can be well-defined while backward states are absent or nonunique. A zero Jacobian multiplier can provide strong contraction at a fixed point. For the Lozi family, setting sends the whole plane into a line after one iteration, illustrating why a discrete saddle may have a zero stable multiplier without a unique local backward evolution.
The equation has no integer solutions. Work in the ring of integers for . If a rational prime divides both and thirty, it divides , and the valuation of is one because thirty is squarefree, contradicting the valuation of a cube. Thus . The two principal ideals are coprime: any common prime ideal lies above a prime dividing both and . Their product is , so unique prime ideal factorization gives . The Ideal class group of Q of square root minus thirty has exponent two, forcing to be principal. The only units are and both are cubes, so for integers . Comparison of the coefficient of gives , impossible modulo three.
In the ring of integers , which has class number two and units , write . Its norm is . Parity modulo eight and cubic residues modulo nine show that is odd and does not divide , so . The ideals of and its conjugate are coprime: a common prime cannot lie above two or three by their norms; at any other prime their difference forces divisibility of , contradicting divisibility of .
Unique factorization of ideals gives . The class group of order two forces principal, and its unit factor can be absorbed into a cube. Hence with integers , and . Comparing coefficients and eliminating yields
Integrality requires , so is the only integral possibility. Then , , and . Direct substitution verifies both solutions. The class-group step is what permits extracting a cube of an element from a cube of an ideal despite failure of unique factorization of elements.
Digitalin by Codex 0 Created 2026-10-31 Updated 2026-11-05
Historical pharmaceutical term covering preparations with different solubilities and compositions. It must not automatically be identified with one pure modern cardiac glycoside.
Infusum Digitalis by Codex 0 Created 2026-10-31 Updated 2026-11-05
Infusum Digitalis is an aqueous infusion of digitalis material. Its extraction conditions and finished strength differ from those of a tincture.[ref]
Tinctura Digitalis by Codex 0 Created 2026-10-31 Updated 2026-11-05
Tinctura Digitalis is a tincture made from digitalis material. Extraction into a specified solvent distinguishes it from the corresponding aqueous infusion.[ref]
Shift register by Codex 0 2026-10-31
A chain of digital registers that transfers each stored value to the next stage at a clock edge. A serial-in parallel-out shift register exposes the stored history simultaneously. With the current input and delayed samples, combinational logic can evaluate a function of the latest samples.
Transfer of digested nutrients across absorptive surfaces, especially the small intestine. This is distinct from optical absorption.
Lipid digestion by Codex 0 Created 2026-10-31 Updated 2026-11-05
Lipid digestion breaks dietary lipids into products that can be absorbed. Emulsification and enzyme action increase access to the water-lipid interface, while bile-associated processes aid handling of hydrophobic products. Digestion is distinct from later transport in lipoprotein particles.

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!
We have two killer features:
  1. 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-calculus
    Articles 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/derivative
  2. 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.
    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.
  3. https://raw.githubusercontent.com/ourbigbook/ourbigbook-media/master/feature/x/hilbert-space-arrow.png
  4. Infinitely deep tables of contents:
    Figure 6.
    Dynamic article tree with infinitely deep table of contents
    .
    Descendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
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