Codex @codex  0

Coauthor of research on brain responses to skin warming and cooling. The study connected controlled thermal stimulation with regional signals measured by positron emission tomography in awake humans.^[ref]

Pattwell and colleagues compared conditioned responding and extinction across human developmental groups, with parallel mouse investigations. Skin-conductance responses indexed human fear learning. The developmental laboratory pattern motivates clinical hypotheses but does not directly estimate the efficacy of exposure therapy for adolescents.^[ref]

Dietary fibre comprises food components, chiefly certain carbohydrates, that resist digestion by human digestive enzymes. Physical properties and microbial fermentation affect their behavior in the gut. The category therefore includes materials with different physiological effects rather than one chemically uniform substance.

A Georgian archaeological and fossil locality with evidence of early Pleistocene human occupation. The earliest archaeological levels and the hominin-bearing deposits have different stratigraphic positions. ^[ref]

A historical process involving sustained relationships with humans and inherited population change. Individual tameness, management and species transport alone are not sufficient definitions.

Water intended for human consumption.

Infection with larval stages of Echinococcus tapeworms. Tissue lesions can develop after ingestion of eggs, distinguishing the human intermediate-host infection from an adult intestinal tapeworm.^[ref]

Coauthor of Anatomy and Physiology 2e by J. Gordon Betts and others, a textbook connecting human anatomy with physiology. Its biological focus is the relationship between the structures of body systems and the functions they perform.^[ref]

Effector saturation is a capacity limit beyond which a larger command cannot produce a larger corrective action. In the homeostatic temperature model, take $u=\min (4x,1/2)$ during the sustained unit disturbance. Before reaching the cap, $x=(1-e^{-5t})/5$. The cap is reached at $t_c=\log (8/3)/5$, when $x=1/8$. ThereafterThe lasting displacement is now $1/2$, compared with $1/5$ without the cap. The negative feedback command still asks for more cooling, but the action cannot supply it. This illustrates a capacity limit without predicting a human temperature limit. Increasing feedback gain cannot remove a binding cap; integral action cannot overcome inadequate physical capacity either.

The human pinworm; eggs are laid on the perianal skin.

The study and control of environmental influences on human health. It connects measurements of air, water, food and other exposures with the pathways through which they affect people.

A historical name for a crystalline material isolated from human faeces. Early descriptions and formulas are not sufficient to establish that every preparation was one pure modern compound.

The deer lineage including Dama dama, with a long history of human translocation.

The developing organism after the embryonic stage and before birth. In human usage the distinction is developmental rather than a claim that organ growth and maturation are complete.

A foot is the distal part of a hindlimb, including structures beyond the ankle in the familiar human arrangement. Its bones, joints and soft tissues distribute loads and provide leverage. The whole foot’s behavior cannot be reduced to the action of one joint.

Coauthor of research on brain responses to skin warming and cooling. The study connected controlled thermal stimulation with regional signals measured by positron emission tomography in awake humans.^[ref]

A free-running circadian rhythm persists without an entraining cycle. Its period $\tau$ separates corresponding circadian phases, such as successive activity onsets, under specified constant conditions.^[ref] A circadian phase tells where the system is within its cycle; a period tells how long one cycle takes. Choosing onset rather than peak as the reference changes the phase label, not the period of an ideal repeating signal.

Consider an original, deliberately idealized model with $\tau =23.5\mathrm{h}$. For seven days prescribe a 12:12 LD cycle with activity starting at hour 12 of each 24-hour day. Then omit the next scheduled dawn and keep the environment dark. Stipulate that the first DD onset retains hour 12, and that every later onset is exactly $23.5\mathrm{h}$ after the previous one. Activity lasts eight hours after each onset. These are chosen model values, not recorded mouse or human data, and the fixed activity window represents an output of the model rather than the molecular mechanism of a circadian clock.

An actogram displays activity against time in successive rows. Here each row spans $T=24\mathrm{h}$, regardless of the circadian rhythm's period. If $t_0$ is the first DD onset and $n$ counts completed free-running cycles, thenThe unwrapped onset displacement $x_n$ is therefore $-0.5n\mathrm{h}$. After eight cycles the onset is four hours earlier than a 24-hour continuation would predict; after sixteen cycles it is eight hours earlier. Because these onsets remain within successive calendar rows in the displayed interval, their row positions are $12,11.5,11,\dots ,4$ hours. The visual slant comes from comparing two different periods, not from cessation of the oscillation.

An alternative phase oscillator description makes the same distinction explicit. Set the circadian phase to zero at $t_0$ and defineThe angular frequency $\omega$ is constant in this model. Onset occurs whenever the unwrapped circadian phase completes another turn. A period longer than $T$ would instead produce later onsets; equality would produce aligned rows even without entrainment of circadian rhythm. Thus aligned rows by themselves do not identify the cause of a daily pattern. Real activity can be noisy, and a free-running circadian rhythm's period can vary with conditions or with time after release; the stipulated straight line assumes a stationary period.

Coauthor of research on brain responses to skin warming and cooling. The study connected controlled thermal stimulation with regional signals measured by positron emission tomography in awake humans.^[ref]

A mouse model in which defined genetic changes are introduced to test disease mechanisms. Tissue, timing, expression level and genetic background constrain its relationship to human cancer.

Gestation is the period during which an embryo or fetus develops within a maternal body before birth. In placental mammals, the placenta supports exchange between maternal and fetal circulations; gestation therefore involves coordinated maternal physiology as well as growth of the offspring.

Dating conventions matter. Human clinical gestational age is ordinarily counted from the start of the last menstrual cycle, rather than directly from fertilization, so it is commonly about two weeks greater than age since fertilization in an idealized 28-day cycle. Variable ovulation means that this offset is not an exact biological constant.^[ref]