Persius/hicric huggingface dataset:
Tracheal rings
The cartilages of the trachea (or tracheal rings) vary from sixteen to twenty in number: each forms an imperfect ring, which occupies the anterior two-thirds or so of the circumference of the trachea, being deficient behind, where the tube is completed by fibrous tissue and unstriped muscular fibers.

# Middle tracheal cartilages
The cartilages are placed horizontally above each other, separated by narrow intervals.
They measure about 4 mm. in depth and 1 mm. in thickness.
Their outer surfaces are flattened in a vertical direction, but the internal are convex, the cartilages being thicker in the middle than at the margins.
Two or more of the cartilages often unite, partially or completely, and they are sometimes bifurcated at their extremities.
They are highly elastic, but may become calcified in advanced life.

# Bronchial cartilages
In the right bronchus the cartilages vary in number from ten to twelve; in the left, from fifteen to twenty.
They are longer and wider than those of the trachea, but have the same shape and arrangement.

# First and last tracheal cartilages
The peculiar tracheal cartilages are the first and the last.
The first cartilage is broader than the rest, and often divided at one end; it is connected by the cricotracheal ligament with the lower border of the cricoid cartilage, with which, or with the succeeding cartilage, it is sometimes blended.
The last cartilage is thick and broad in the middle, in consequence of its lower border being prolonged into a triangular hook-shaped process, which curves downward and backward between the two bronchi. It ends on each side in an imperfect ring, which encloses the commencement of the bronchus. The cartilage above the last is somewhat broader than the others at its center.

# Additional images
- Front view of cartilages of larynx, trachea, and bronchi.
- Bronchi and bronchioles. The lungs have been widely separated and tissue cut away to expose the air-tubes.
Cayenne pepper
The Cayenne is a red, hot chili pepper used to flavor dishes, and for medicinal purposes. Named for the city of Cayenne in French Guiana, it is a cultivar of Capsicum annuum related to bell peppers, jalapenos, and others.  The Capsicum genus is in the nightshade family (Solanaceae).
The fruits are generally dried and ground, or pulped and baked into cakes, which are then ground and sifted to make the powder, Cayenne pepper.
Cayenne is used in cooking spicy hot dishes, as a powder or in its whole form (such as in Szechuan cuisine) or in a thin, vinegar-based sauce. It is generally rated at 30,000 to 50,000 Scoville Units. It is also used as a herbal supplement, and was mentioned by Nicholas Culpeper in his Complete Herbal.

# Medicinal Purpose
The potent, hot fruit of cayenne has been used as medicine for centuries.
In addition, it has been used for the following problems:
- Gastrointestinal tract: including stomachaches, cramping pains, and gas.
- Diseases of the circulatory system: It is still traditionally used in herbal medicine as a circulatory tonic.
- Rheumatic and arthritic pains: Rubbed on the skin it causes a counterirritant effect.  A counterirritant is something which causes irritation to the area to which it is applied.  This makes it distract the nerves from the original irritation (such as joint pain in the case of arthritis).
- Sore throat: If gargled with water it can work as an effective treatment for sore throats.
- Styptic: Application of cayenne powder has traditionally been considered to have a powerful coagulating ability.
- Thermogenic: Cayenne pepper is used both internally and externally in colder climates to protect against frostbite, it may be used in a crushed or powdered form in socks or taken internally in a tea to increase body temperature and circulation to the extremities.

# Active components
Cayenne contains a pungent resin-like substance known as capsaicin.  This chemical, the active ingredient of pepper spray or mace, relieves pain and itching by affecting sensory nerves.  Capsaicin temporarily causes various neurotransmitters to release from these nerves, leading to their depletion.  Without the neurotransmitters, pain signals can no longer be sent. The effect is temporary.
Capsaicin and other constituents in cayenne have been shown to have several other actions, including reducing platelet stickiness and acting as antioxidants.

# Cultivation
Cayenne pepper is considered to be misnomer by the American Spice Trade Association, which prefers the more generic term red pepper.  Generally speaking any of a number of peppers are called cayenne.  Capsicum frutescens can be grown in a variety of locations and needs approximately 100 days to mature.  Peppers prefer warm, moist, nutrient-rich soil in a warm climate.  The plants grow to about 2-4 feet of height and should be spaced three feet apart.

# References and notes
-  WHFoods: Chili pepper, dried
-  Growing: Cayenne
Celiac ganglia
The Celiac Ganglia (semilunar ganglia) are two large irregularly shaped masses having the appearance of lymph glands and placed one on either side of the middle line in front of the crura of the diaphragm close to the suprarenal glands, that on the right side being placed behind the inferior vena cava. The celiac ganglion is part of the sympathetic prevertebral chain possessing a great variety of specific receptors and neurotransmitters such as catecholamines, neuropeptides, and nitric oxide and constitutes a modulation center in the pathway of the afferent and efferent fibers between the central nervous system and the ovary. The main preganglion neurotransmitter of the celiac ganglion is acetylcholine, yet the celiac ganglion-mesenteric complex also contain  and  adrenergic receptors and is innervated by fibers of adrenergic nature that come from other preaortic ganglia.
The upper part of each ganglion is joined by the greater splanchnic nerve, while the lower part, which is segmented off and named the aorticorenal ganglion, receives the lesser splanchnic nerve and gives off the greater part of the renal plexus.
These ganglion contain neurons whose unmyelinated postganglionic axons innervate the stomach, liver, gallbladder, spleen, kidney, small intestine, and the ascending and transverse colon. They directly innervate the ovarian theca and secondary interstitial cells and exert an indirect action on the luteal cells. It is sometimes referred to as the semilunar ganglion or the solar ganglion.

# Links to Ovary
Modifications in the adrenergic activity of the celiac ganglion results in an altered capacity of the ovary of pregnant rats to produce progesterone, suggesting that the celiac ganglion-superior ovarian nerve-ovarian axis provides a direct link between the autonomic nervous system and the physiology of pregnancy. It has also been shown that modifications in the cholinergic input at the celiac ganglion also led, via the superior ovarian nerve, to modifications in ovarian steroidogenesis. Most of the fibers of the superior ovarian nerve come from the postganglionic sympathetic neurons of the celiac ganglion.

# Additional images
- Diagram of efferent sympathetic nervous system.
- Abdominal portion of the sympathetic trunk, with the celiac and hypogastric plexuses.
- Lower half of right sympathetic cord.
Central moment
In probability theory and statistics, the kth moment about the mean (or kth central moment) of a real-valued random variable X is the quantity E)k], where E is the expectation operator. Some random variables have no mean, in which case the moment about the mean is not defined. The kth moment about the mean is often denoted k.  For a continuous univariate probability distribution with probability density function f(x) the moment about the mean  is
\mu_k
= \left\langle ( X - \langle X \rangle )^k \right\rangle
= \int_{-\infty}^{+\infty} (x - \mu)^k f(x)\,dx.
Note that \langle X \rangle is equivalent to E(X) (i.e the expectation of X); it is the notation preferred by physicists.
Sometimes it is convenient to convert moments about the origin to moments about the mean.  The general equation for converting the nth-order moment about the origin to the moment about the mean is
\mu_n = \sum_{j=0}^n {n \choose j} (-1) ^{n-j} \mu'_j m^{n-j},
where m is the mean of the distribution, and the moment about the origin is given by
\mu'_j = \int_{-\infty}^{+\infty} x^j f(x)\,dx.
The first moment about the mean is zero. The second moment about the mean is called the variance, and is usually denoted 2, where  represents the standard deviation. The third and fourth moments about the mean are used to define the standardized moments which are used to define skewness and kurtosis, respectively.
For n  2, the nth central moment is translation-invariant, i.e. for any random variable X and any constant c, we have
For all n, the nth central moment is homogeneous of degree n:
Only for n  3 do we have an additivity property for random variables X and Y that are independent:
A related functional that shares the translation-invariance and homogeneity properties with the nth central moment, but continues to have this additivity property even when n  4 is the nth cumulant n(X).  For n = 1, the nth cumulant is just the expected value; for n = either 2 or 3, the nth cumulant is just the nth central moment; for n  4, the nth cumulant is an nth-degree monic polynomial in the first n moments (about zero), and is also a (simpler) nth-degree polynomial in the first n central moments.

# Central moments 2, 3, and 4
As mentioned above, the second central moment is the variance, and the third and fourth central moments are related to the skewness and kurtosis, respectively. It is therefore useful to have the formulae for these central moments in terms of the moments about the origin. These are:
where m is the mean, as before.
Cephalhematoma
Synonyms and keywords: Cephalhaematoma

# Overview
A cephalhematoma is a hemorrhage of blood between the skull and the periosteum of a newborn baby secondary to rupture of blood vessels crossing the periosteum.  Because the swelling is subperiosteal its boundaries are limited by the individual bones, in contrast to a chignon.

# Causes
The usual causes of a cephalhematoma are a prolonged second stage of labor or instrumental delivery, particularly ventouse.

# Differential Diagnosis
Cephalhematoma should be distinguished from another scalp bleeding called Subgaleal hemorrahge (also called Subaponeurotic Hemorrhage), which is blood between the scalp and skull bone (above the periosteum) and is more extensive. It is more prone to complications, especially anemia and bruising.

# Diagnosis

## History and Symptoms
If severe the child may develop jaundice, anemia or hypotension.  In some cases it may be an indication of a linear skull fracture or be at risk of an infection leading to osteomyelitis or meningitis.
The swelling of a Cephalhematoma takes weeks to resolve as the blood clot is slowly absorbed from the periphery towards the centre. In time the swelling hardens (calcification) leaving a relatively softer centre so that it appears as a 'depressed fracture'.

## Lab tests
No laboratory studies usually are necessary.

## Imaging studies
Skull X-ray or CT scanning is used if neurological symptoms appear. Skull radiography or CT scanning is also used if concomitant depressed skull fracture is a possibility.

# Treatment
Usual management is mainly observation. Transfusion and phototherapy are necessary if blood accumulation is significant. Aspiration is more likely to increase the risk of infection. The presence of a bleeding disorder should be considered.
Cerium oxalate

# Overview
Cerium(III) oxalate or cerous oxalate is the inorganic cerium salt of oxalic acid. It is a white crystalline solid with the chemical formula of Ce2(C2O4)3. It could be obtained by the reaction of oxalic acid with cerium(III) chloride.

# Uses
Cerium(III) oxalate is used as an antiemetic. It has been identified as part of the invisible ink that was used by Stasi operatives during the Cold War.

# Toxicity
Cerium(III) oxalate irritates skin and mucous membranes, and is a strong irritant to eyes. If it gets into the eyes, there is a danger of severe eye injury.
Cerium salts increase the blood coagulation rate, and exposure to cerium salts can cause sensitivity to heat.
Oxalates are corrosive to tissue and are powerful irritants. They have a caustic effect on the linings of the digestive tracts and can cause kidney damage.
Cohen syndrome
Synonyms and keywords: Pepper syndrome, Cervenka syndrome, Hypotonia obesity and prominent incisors, Norio syndrome, Obesity-hypotonia syndrome, Prominent incisors-obesity-hypotonia syndrome

# Overview
Cohen syndrome is characterized by obesity, mental retardation and craniofacial dysmorphism.

# Historical Perspective
Cohen syndrome named after Michael Cohen, William Pepper and Jaroslav Cervenka, who researched the illness.

# Pathophysiology
Cohen syndrome has an autosomal recessive transmission with variable expression. It is believed to be a gene mutation at locus 8q22 gene COH1.

# Diagnosis
The signs and symptoms vary due to variable expression.  There are variable degrees of mental retardation with occasional seizure and deafness in Cohen syndrome.

## Physical Examination
General appearance is one of obesity with thin/elongated arms and legs.

### Eyes
Ocular complications, though rare, are:
- Hemeralopia (decreased vision in bright light)
- iris/retinal coloboma
- Microphthalmia
- Myopia
- Nystagmus
- Optic atrophy
- Pigmentary chorioretinitis
- Strabismus

### Mouth
- Micrognathia
- Short philtrum
- High vaulted palate
Cervical sinus
The mandibular and hyoid arches grow more rapidly than those behind them, with the result that the latter become, to a certain extent, telescoped within the former, and a deep depression, the cervical sinus, is formed on either side of the neck.
This sinus is bounded in front by the hyoid arch, and behind by the thoracic wall; it is ultimately obliterated by the fusion of its walls.

# Additional images
- The head and neck of a human embryo thirty-two days old, seen from the ventral surface.
Charge carrier
In physics, a charge carrier denotes a free (mobile, unbound) particle carrying an electric charge. Examples are electrons and ions.  In semiconductor physics, the travelling vacancies in the valence-band electron population (holes) are treated as charge carriers.
In ionic solutions, the charge carriers are the dissolved cations and anions. Similarly, cations and anions of the dissociated liquid serve as charge carriers in liquids and melted ionic solids (see eg. the Hall-Heroult process for an example of electrolysis of a melt).
In plasma, such as an electric arc, the electrons and cations of ionized gas and vaporized material of electrodes act as charge carriers. (The electrode vaporization occurs in vacuum too, but then the arc is not technically occurring in vacuum, but in low-pressure electrode vapors.)
In vacuum, in an electric arc or in vacuum tubes free electrons act as charge carriers.
In metals, the charge carriers are the electrons forming the Fermi gas in the metal lattice.

# Majority and minority carriers in semiconductors
In semiconductors, electrons and holes act as charge carriers. The more abundant charge carriers are called majority carriers. In N-type semiconductors they are electrons, while in P-type semiconductors they are holes. The less abundant charge carriers are called minority carriers; in N-type semiconductors they are holes, while in P-type semiconductors they are electrons.
Minority carriers play an important role in bipolar transistors and solar cells. However, their role in field-effect transistors (FETs) is a bit more complex: for example, a MOSFET has both P-type and N-type regions. The transistor action involves the majority carriers of the source and drain regions, but these carriers traverse the body of the opposite type, where they are minority carriers. However, the traversing carriers hugely outnumber their opposite type in the transfer region (in fact, the opposite type carriers are removed by an applied electric field that creates a depletion layer), so conventionally the source and drain designation for the carriers is adopted, and FETs are called "majority carrier" devices.
When an electron meets with a hole, they recombine and these free carriers effectively vanish. The energy released can be either thermal, heating up the semiconductor (thermal recombination, one of the sources of waste heat in semiconductors), or released as photons (optical recombination, used in LEDs and semiconductor lasers).
Charge density
The linear, surface, or volume charge density is the amount of electric charge in a line, surface, or volume. It is measured in coulombs  per metre (C/m), square metre (C/m2), or cubic metre (C/m3), respectively. Since there are positive as well as negative charges, the charge density can take on negative values. Like any density it can depend on position. It should not be confused with the charge carrier density. As related to chemistry, it can refer to the charge distribution over the volume of a particle, molecule, or atom.  Therefore, a lithium cation will carry a higher charge density than a sodium cation due to its smaller ionic radius.

# Classical charge density

## Continuous charges
The integral of the charge density \alpha_q(\mathbf r), \sigma_q(\mathbf r), \rho_q(\mathbf r) over a line l, surface S, or volume V, is equal to the total charge Q of that region, defined to be: 
This relation defines the charge density mathematically. Note that the symbols used to denote the various dimensions of charge density vary between fields of studies. Other commonly used notations are \lambda, \sigma, \rho; or \rho_l, \rho_s, \rho_v for (C/m), (C/m2), (C/m3) and respectively.

## Homogeneous charge density
For the special case of a homogeneous charge density, that is one that is independent of position, equal to \rho_{q,0} the equation simplifies to:
The proof of this is simple. Start with the definition of the charge of any volume:
Then, by definition of homogeneity, \rho_q(\mathbf r) is a constant that we will denote \rho_{q,0} to differentiate between the constant and non-constant forms, and thus by the properties of an integral can be pulled outside of the integral resulting in:
Again, by the properties of integrals:
Therefore by substitution:
Which leads to:
Which is precisely the result mentioned above for volume charge density. The equivalent proofs for linear charge density and surface charge density follow the same arguments as above.

## Discrete charges
If the charge in a region consists of N discrete point-like charge carriers like electrons the charge density can be expressed via the Dirac delta function, for example, the volume charge density is:
Here, and \mathbf r_i the position of the ith charge carrier. If all charge carriers have the same charge q (for electrons q=-e) the charge density can be expressed through the charge carrier density
n(\mathbf r):
Again, the equivalent equations for the linear and surface charge densities follow directly from the above relations.

# Quantum charge density
In quantum mechanics, charge density is related to wavefunction  \psi(\mathbf r) by the equation
when the wavefunction is normalized as

# Application
The charge density appears in the continuity equation which follows from Maxwell's Equations in the electromagnetic theory.
Chiari network
The Chiari network is a filamentous structure seen in the right atrium.

# History
The Chiari network was first described in 1897 in an autopsy series by Dr Chiari.

# Prevalence
The Chiari network was noted to be present in 2-3% of the population. It was detected in approximately 1.5% of transthoracic echocardiographic studies in a series in 1984. Technical improvements in image quality may have increased the incidence of its detection.

# Pathophysiology
The Chiari network is an embryological remnant of one of the valves of sinus venosus. This embryonic remnant has no known purpose and is not pathological. Although the Chiari network has no clinical significance, it must be distinguished from other pathological masses in the right atrium including thrombus, vegetation, and myxoma.
The Chiari network appears to be a web-like structure with a variable number of thread-like components.
Chiari network is characterized by whip-like motion within the right atrium and attachment to the wall of the right atrium in close proximity to the entrance of the inferior vena cava.

# Diagnosis
Entrapment of catheters during right heart catheterization has been reported.

## Echocardiography
-133535547003356906&hl=en
8805973032893590466&hl=en
5824301041073753290&hl=en
2322002432861561956&hl=en

## Autopsy Findings
Images courtesy of Professor Peter Anderson DVM PhD and published with permission  PEIR, University of Alabama at Birmingham, Department of Pathology
- Chiari Network: Gross; fixed tissue, close-up of coronary sinus with fenestrae in valve
- Chiari Network: Gross; fixed tissue, close-up view, an excellent example

# Additional Resources
- JA Werner, MD Cheitlin, BW Gross, SM Speck and TD Ivey. Echocardiographic appearance of the Chiari network: differentiation from right-heart pathology. Circulation 1981, Vol 63, 1104-1109,
- H. Tanaka, K. Ueda, M. Murakami, S. Hasegawa, and M. Sunamori A prominent Chiari network Ann. Thorac. Surg., June 1, 2002; 73(6): 1985 - 1985.
- D. M. Payne, R. J. F. Baskett, and G. M. Hirsch Infectious endocarditis of a Chiari network Ann. Thorac. Surg., October 1, 2003; 76(4): 1303 - 1305.
- H. Hara, R. Virmani, E. Ladich, S. Mackey-Bojack, J. Titus, M. Reisman, W. Gray, M. Nakamura, M. Mooney, A. Poulose, et al. Patent Foramen Ovale: Current Pathology, Pathophysiology, and Clinical Status J. Am. Coll. Cardiol., November 1, 2005; 46(9): 1768 - 1776.