Persius/hicric huggingface dataset:
Cervical dilation

# Overview
Cervical dilation is the dilation (opening) of the cervix during childbirth. In the later stages of pregnancy, the cervix may already have opened up to 1-3 cm (or more in rarer circumstances), but during labor, repeated uterine contractions lead to further widening of the cervix to about 6 centimeters.  From that point, pressure from the presenting part (head in vertex births or bottom in breech births), along with uterine contractions, will dilate the cervix to 10 centimeters, which is "complete." Cervical dilation is accompanied by effacement, the thinning of the cervix.

# Guidelines
General guidelines for cervical dilation:
- Early Labor: 0-3 centimeters
- Active Labor: 4-7 centimeters
- Transition: 8-10 centimeters
- Complete: 10 centimeters. Expulsion of the fetus takes place shortly after this stage is reached (although the mother does not always push right away.)
During pregnancy, the os (opening) of the cervix is blocked by a thick plug of mucus to prevent bacteria from entering the uterus. During dilation, this plug is loosened. It may come out as one piece, or as thick mucous discharge from the vagina. When this occurs, it is an indication that the cervix is beginning to dilate, although not all women will notice this mucus plug being released.
Bloody show is another indication that the cervix is dilating. Bloody show usually comes along with the mucus plug, and may continue throughout labor, making the mucus tinged pink, red or brown. Fresh, red blood is usually not associated with dilation, but rather serious complications such as placental abruption, or placenta previa.  Red blood in small quantities often also follows an exam.
Prostaglandins contribute to cervical ripening and dilation. The body produces these naturally. Sometimes prostaglandins in synthesized forms are applied directly to the cervix during labor induction to soften the cervix, though these medications have been linked to an increase in uterine rupture risk especially for those with previous cesarean sections.
The pain experienced during dilation is similar to that of menstruation (although markedly more intense), as period pains are thought to be due to the passing of endometrium through the cervix. Most of the pain during labor is caused by the cervix dilating, not the uterus contracting.
Sympathetic trunk

# Overview
The sympathetic trunk (sympathetic chain, gangliated cord) is a bundle of nerve fibers that runs from the base of the skull to the coccyx.  There are two sympathetic trunks in the body, a right one and a left one.

# Structure
The sympathetic trunk travels inferiorly from the skull, just lateral to the vertebral bodies.  It interacts with the spinal nerves or their ventral root by way of rami communicantes.
The superior end of it is continued upward through the carotid canal into the skull, and forms a plexus on the internal carotid artery; the inferior part travels in front of the coccyx, where it converges with the other trunk at a structure known as the ganglion impar.
Along the length of the sympathetic trunk are ganglia known as paravertebral ganglia.

# Function
The sympathetic trunk is a fundamental part of the sympathetic division of the autonomic nervous system.  It allows nerve fibers to travel to spinal nerves that are superior and inferior to the one in which it originated.  Also, a number of nerves, such as most of the splanchnic nerves, arise directly from the trunks.

# Additional images
- The formation of the spinal nerve from the dorsal and ventral roots.
- Transverse section of thorax, showing relations of pulmonary artery.
- Dissection of side wall of pelvis showing sacral and pudendal plexuses.
- Sacral plexus of the right side.
Chain of survival

# Overview
The chain of survival refers to a series of actions that, when put into motion, reduce the mortality associated with cardiac arrest. Like any chain, the chain of survival is only as strong as its weakest link. The four interdependent links in the chain of survival are early access, early CPR, early defibrillation, and early advanced care.

# Etymology
The phrase "chain of survival" was first used as a slogan for the 1988 Conference on Citizen CPR. It then appeared in JEMS editorial in August 1989, and the first issue of Currents in Emergency Cardiac Care in 1990. The concept was elaborated in the American Heart Association's 1992 guidelines for cardiopulmonary resuscitation and emergency cardiac care, and then echoed by the International Liaison Committee on Resuscitation (ILCOR) in 1997.

# Early access
Someone must witness the cardiac arrest and activate the EMS system with an immediate call to 9-1-1 (or your local emergency number).

# Early CPR
In order to be most effective, bystander CPR should be provided immediately after collapse of the patient. Properly performed CPR can keep the heart in VF for 10-12 minutes longer.

# Early defibrillation
Most adults who can be saved from cardiac arrest are in ventricular fibrillation or pulseless ventricular tachycardia. Early defibrillation is the link in the chain most likely to improve survival. Public access defibillation may be the key to improving survival rates in out-of-hospital cardiac arrest, but is of the greatest value when the other links in the chain do not fail.

# Early advanced care
Early advanced cardiac life support by paramedics is another critical link in the chain of survival. In communities with survival rates > 20%, a minimum of two of the rescuers are trained to the advanced level. In some countries, EMS delivery may be performed by ambulancemen, nurses, or doctors.
Yield (chemistry)
In chemistry, yield, also referred to as chemical yield and reaction yield, is the amount of product obtained in a chemical reaction. The absolute yield can be given as the weight in grams or in moles (molar yield). The fractional yield or relative yield, which serve to measure the effectiveness of a synthetic procedure, is calculated by dividing the amount of the obtained product in moles by the theoretical yield in moles:
To obtain a percentage yield, multiply the fractional yield by 100% (e.g., 0.673 = 67.3%).
One or more reactants in a chemical reaction are often used in excess. The theoretical yield is therefore calculated based on the molar amount of the limiting reactant, taking into account the stoichiometry of the reaction. For the calculation it is usually assumed that there is only one reaction involved.
The ideal or theoretical yield of a chemical reaction would be 100%, a value that is impossible to achieve in a practical setting. According to Vogel's Textbook of Practical Organic Chemistry, yields around 100% are called quantitative, yields above about 90% are called excellent, yields above about 80% very good,  yields above about 70% are called good, yields below about 50% are called fair, yields below about 40% are called poor. Yields may appear to be above 100% when products are impure. Purification steps always lower the yield and the reported yields usually refer to the yield of the final purified product.
Child development

# Overview
Child development is the study or examination of mechanisms that operate during the biological and psychological process of growth of a child to adolescence, from dependency to increasing autonomy. Pediatrics is the branch of medicine relating to the care of children. Age-related development terms are: Infant or baby (ages 0 - 1.5) (including neonate or newborn), toddler (ages 1.5 - 4); child; preadolescence up to adolescence and puberty.
The optimal development of children is vital to society.  Therefore the social, cognitive, emotional, and educational development of children is important to understand.  Increased research and interest in this field has resulted in new theories and strategies, with specific regard to developmentally appropriate practice within the school system.

# Milestones
Milestones are the specific physical and mental abilities (such as walking and understanding language) according to age of a child.  Milestones are the major focus of Child development stages.
Milestones can be described as what a child accomplishes throughout the different stages in their life.  An example of this would be eye-hand coordination, which includes a child's increasing ability to manipulate objects in a coordinated manner.  Increased knowledge of age-specific milestones allow parents and other caring adults to keep track of appropriate development.
Crucial aspects of child development include: patience, problem solving, social skills, and creativity.  All of these traits should be taught at a young age and practiced frequently.
A common concern in child development is developmental delay.  This concern involves a delay in age-specific ability for important developmental milestones.  Early intervention and prevention of developmental delay are the major focus of research in child development.
Chin augmentation

# Overview
Chin augmentation using surgical implants can alter the underlying structure of the face, providing better balance to the facial features. This operation is often performed at the time of rhinoplasty to help balance the facial proportions.
Chin implants are to build a better profile.
Patients own bone is donated from ribs and from part of the pelvis (the ilium.) Unfortunately, use of donated bone implants in chin augmentation, even the patients own, appears to be associated with a higher rate of infection, even after the implant has been in place for decades.
Chin augmentation is still popular because its a relatively easy operation for both surgeon and patient while producing dramatic and noticeable changes in the silhouette of the face. This type of surgery is usually performed by an oral and maxillofacial surgeon.

# Potential risks and side effects
The usual complications are relatively minor and include swelling, hematoma (blood pooling) and numbness of the lower lip which usually does not last long. Other, less common risks include infection, bony changes and displacement of the implant.

# Chemical compositions
Gore-tex used in plastic surgery and other operations is known by an abbreviation of its chemical name, ePTFE (expanded polytetrafluoroethylene) or Gore S.A.M. (subcutaneous augmentation material.)
ePTFE is used in medicine because it is biocompatible and does not cause problems inside the human body. Because ePTFE is flexible and soft but very strong, it is inserted during operations in trimmed sheets and carved blocks and held to the bone by titanium screws. But because the material is porous, the force that really holds the implant in place is soft tissue and bone growing through and into the implant.
Another chin augmentation implant material is commercially known as AlloDerm and known to physicians as acellular human cadavertic derms.  AlloDerm comes from tissue donors; just after death, technicians remove a thin layer of skin and use antibiotics and other substances to remove the cells and donor DNA that may cause rejection. The graft that emerges is often used to cover chin implants. Other typical types of chin implants include silicone implants in varying degrees of softness; silicone elastomers (any of various polymers having the elastic properties of natural rubber) and porous polyethylene implants. 
Other common implant materials include Supramid, a braided nonabsorbale synthetic suture material in polymer shell and Mersiline, a mesh-like material that provides a scaffold on the bone.
Phenacyl chloride

# Overview
Phenacyl chloride is a substituted acetophenone. It is a useful building block in organic chemistry. Apart from that, it has been historically used as a riot control agent, where it is designated CN.

# Preparation
Phenacyl chloride is readily available commercially. It may be synthesized by the Friedel-Crafts acylation of benzene using chloroacetyl chloride, with an aluminium chloride catalyst:

# Riot control agent
It was investigated, but not used, during the First and Second World Wars.
Because of its significantly greater toxicity, it has largely been supplanted by CS gas. Even though CN is still supplied to paramilitary and police forces in a small pressurized aerosol known as Mace or tear gas, its use is falling as pepper spray both works and disperses more quickly than CN.
The term "Mace" came into being because it was the brand-name invented by one of the first American manufacturers of CN aerosol sprays. Subsequently, Mace became synonymous with tear-gas sprays in the same way that Kleenex has become strongly associated with tissue papers (a phenomenon known as a genericized trademark).
Like CS gas, this compound irritates the mucous membranes (oral, nasal, conjunctival and tracheobronchial). Sometimes it can give rise to more generalized reactions such as syncope, temporary loss of balance and orientation. More rarely, cutaneous irritating outbreaks have been observed and allergic contact permanent dermatitis.
At high concentrations CN has caused corneal epithelial damage and chemosis. It has also accounted for at least five deaths, which have resulted from pulmonary injury and/or asphyxia.
Chloroalkyl ether

# Overview
Chloroalkyl ethers are a class of organic compounds with the general structure R-O-(CH2)n-Cl, characterized as an ether connected to a chloromethyl group via a alkane chain
Chloromethyl methyl ether (CMME) is an ether with the formula Template:MethylTemplate:OxygenTemplate:CarbonTemplate:HydrogenTemplate:Chlorine. It is used as an alkylating agent and industrial solvent to manufacture dodecylbenzyl chloride, water repellents, ion-exchange resins, polymers, and as a chloromethylation reagent. It is a known human carcinogen . In organic synthesis the compound is used for the introduction of the methoxymethyl(MOM) protecting group.
Closely related compounds of industrial importance are bis(chloromethyl ether) (BCME) (closely related to chemical weapon sulfur mustard)  and benzyl chloromethyl ether.

# MOM ethers
Methyl chloromethyl ether (often abbreviated MOMCl) is used as a protecting group for alcohols. The product formed is a MOM ether. A base such as N,N-diisopropylethylamine is a requirement.
The MOM group can be removed by application of dilute acid.
An example is the protection of a phenol group :
With a benzyl group the protective group becomes a BOM-ether. See also the closely related methylthiomethyl ethers.
Chordae tendineae

# Overview
The chordae tendineae, or heart strings, are cord-like tendons that connect the papillary muscles to the tricuspid valve and the mitral valve in the heart.
When the right ventricle of the heart contracts, the blood pressure pushes the tricuspid valve which closes and prevents a backflow of blood into the right atrium. The chordae tendineae prevents the flaps from being everted into the right atrium. Similarly, these cord-like tendons hold in position other flaps like the bicuspid or mitral valve.
Chordae tendineae are approximately 80% collagen, while the remaining 20% is made up of elastin and endothelial cells.
Chromium trioxide
The acid anhydride of chromic acid is chromium trioxide or chromium(VI) oxide; industrially, this compound is sometimes sold as "chromic acid".
This compound is an intensely-colored dark red/orange brown, water-soluble, granular solid which is stable by itself, but is a strong oxidant which will react when mixed with many things that can be oxidized. Ethanol, for example, will ignite on contact with it.

# Production
Chromium trioxide is produced commercially by the reaction of sodium dichromate with concentrated sulfuric acid.

# Structure and chemistry
Chromium trioxide consists of chains of tetrahedrally coordinated chromium atoms that share vertices. Each chromium atom therefore has "half share of two oxygen atoms" and two oxygen atoms that are not shared, giving an overall stoichiometry of 1:3.
Chromium trioxide decomposes above 197C liberating oxygen eventually giving Cr2O3. The reaction of chromium trioxide with organic substances is potentially explosive. In spite of this, CrO3 is used in organic chemistry as an oxidant, often dissolved in acetic acid, or acetone in the case of the Jones oxidation.

# Safety
Chromium trioxide is highly toxic, corrosive, and carcinogenic.
Chronic (medical)

# Overview
In medicine, a chronic disease is a disease that is long-lasting or recurrent. The term chronic describes the course of the disease, or its rate of onset and development.  A chronic course is distinguished from a recurrent course; recurrent diseases relapse repeatedly, with periods of remission in between.  As an adjective, chronic can refer to a persistent and lasting medical condition. Chronicity is usually applied to a condition that lasts more than three months.

# Chronic Disease
The definition of a disease or causative condition may depend on the disease being chronic, and the term chronic will often, but not always appear in the description:
- Chronic fatigue syndrome
- Chronic osteoarticular diseases: rheumatoid arthritis, osteoarthritis
- Chronic respiratory diseases: chronic obstructive pulmonary disease, asthma
- Chronic renal failure
- Diabetes mellitus
- Chronic Hepatitis
- Autoimmune diseases, like lupus erythematosus
- Cardiovascular diseases: heart failure, ischemic cardiomyopathy, cerebrovascular disease
- Neoplasic diseases not amenable to be cured
- Osteoporosis

# Treatment
Many chronic diseases require chronic care management for effective long-term treatment.

# Related Chapters
- Acute (medicine)
- Homeopathic theory of chronic diseases
- Chronic pain
- Course (medicine)
- Disease management (health)
Churchwarden Pipe
"Churchwarden" is a term used to describe tobacco pipes with long stems.  Some Churchwarden pipes can be as long as 16 inches (40cm). They range from being straight to curved like a saxophone. Churchwarden pipes are most well known for their similar appearance to the pipes used in the books and films The Lord of the Rings.
Such pipes were very popular as an Oriental influence from the 17th century onwards in Europe. They remained most popular in Eastern Europe, as an emblem of the "Hussars", cavalry troops with roots in the Austro-Hungarian Empire, who went from Russia to France & England during the Napoleonic Wars and brought the pipes with them. It was even known as the "Hussar pipe" at the time. Historical engravings are full of men who loved having their portraits made while enjoying such a smoking instrument. This long stem pipe type has its origins in the Ottoman Empire, geographically and historically.
Churchwarden pipes generally produce a cooler smoke due to the distance smoke must travel from the bowl to the mouthpiece.  They have the added benefit of keeping the users face further away from the heat and smoke produced by combustion in the bowl.  They are also more prone to breakage since more pressure is placed on the tenon when the pipe is supported around the mouthpiece.
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Ciliary processes
The ciliary processes are formed by the inward folding of the various layers of the choroid, i.e., the choroid proper and the lamina basalis, and are received between corresponding foldings of the suspensory ligament of the lens.

# Anatomy
They are arranged in a circle, and form a sort of frill behind the iris, around the margin of the lens. jhg
They vary from sixty to eighty in number, lie side by side, and may be divided into large and small; the former are about 2.5 mm. in length, and the latter, consisting of about one-third of the entire number, are situated in spaces between them, but without regular arrangement.
They are attached by their periphery to three or four of the ridges of the orbiculus ciliaris, and are continuous with the layers of the choroid: their opposite extremities are free and rounded, and are directed toward the posterior chamber of the eyeball and circumference of the lens.
In front, they are continuous with the periphery of the iris.
Their posterior surfaces are connected with the suspensory ligament of the lens.

# Function
The ciliary processes produce aqueous humor.
Clinical endpoint
In a research trial, a clinical endpoint refers to a disease, symptom, or sign that constitutes one of the target outcomes of the trial.  The results of a clinical trial generally indicate the number of people enrolled who reached the pre-determined clinical endpoint during the study interval, compared with the overall number of people who were enrolled.  Once a patient reaches the endpoint, he or she is generally excluded from further experimental intervention (the origin of the term endpoint).
For example, a clinical trial investigating the ability of a medication to prevent heart attack might use chest pain as a clinical endpoint.  Any patient enrolled in the trial who develops chest pain over the course of the trial, then, would be counted as having reached that clinical endpoint.   The results would ultimately reflect the fraction of patients who reached the endpoint of having developed chest pain, compared with the overall number of people enrolled.
When an experiment involves a control group, the fraction of individuals who reach the clinical endpoint after an intervention is compared with the fraction of individuals in the control group who reached the same clinical endpoint, thus reflecting the ability of the intervention to prevent the endpoint in question.

# Primary Endpoint
The primary endpoint is defined as the main result measured at the end of a study to see if a given treatment has worked. For example, researchers might look at survival or risk of recurrence as primary endpoints. The study then compares these factors in the treatment group and the control group. The primary endpoints need to be determined before the study begins.

# Secondary Endpoint
The secondary endpoint is defined as an endpoint other than the primary endpoint that is of interest in a clinical trial. If the difference between treatment groups in the primary endpoint is not significant, the interpretation of significant differences in secondary endpoints may be difficult to interpret because of the multiple comparisons made. It has been proposed that the comparison in the primary endpoint use a significance level of alpha and that the secondary endpoints be evaluated using a significance level alpha/(k + 1), where k is the number of secondary outcomes to be evaluated. Similar to the primary endpoint, the secondary endpoints should also be pre-specified.

# Composite Endpoint
Some studies will examine the incidence of a combined endpoint, which can merge a variety of outcomes into one group.  For example, the heart attack study above may report the incidence of the combined endpoint of chest pain, myocardial infarction, or death.