Persius/hicric huggingface dataset:
Silver oxide
Silver oxide is the chemical compound with the formula Ag2O.  It is a fine black or dark brown powder that is used to prepare other silver compounds.

# Preparation
Silver oxide is commercially available. It can be easily prepared by combining aqueous solutions of silver nitrate and an alkali hydroxide. Noteworthy is the fact that this reaction does not afford appreciable amounts of silver hydroxide due to the favorable energetics for the following reaction:

# Properties
Like most binary oxides, Ag2O is a three-dimensional polymer with covalent metal-oxygen bonding.  It is therefore expected that Ag2O is insoluble in all solvents, except by reaction.  It is also slightly soluble in aqueous solution due to the formation of the ion, Ag(OH)2 and possibly related hydrolysis products.   It hydrolyzes only slightly in water (1 part in 40,000) and dissolves in ammonium hydroxide solution to give soluble derivatives.
A slurry of Ag2O is readily attacked by acids:
where HX = HF, HCl, HBr, or HI, HO2CCF3. It will also react with solutions of alkali chlorides to precipitate silver chloride, leaving a solution of the corresponding alkali hydroxide.
Like many silver compounds, silver oxide is photosensitive.  It also decomposes at temperatures above 280 C.

# Applications
Silver oxide is used in a silver-oxide battery.  Silver oxide reacts easily with ligand precursors such as 1,3-disubstituted imidazolium or benzimidazolium salts to generate the corresponding N-heterocyclic carbene complexes. These silver complexes are useful as carbene-transfer agents, easily displacing labile ligands such as cyclooctadiene or acetonitrile. This is a common way of synthesizing transition metal carbene complexes.
Silver stain

# Overview
Silver staining is the use of silver to stain histologic sections. This kind of staining is important especially to show proteins (for example type III collagen) and DNA. It is used to show both substances inside and outside cells. Silver staining is also used in temperature gradient gel electrophoresis and in polyacrylamide gels.
Some cells are argentaffin. These reduce silver solution to metallic silver after formalin fixation. Other cells are argyrophilic. These reduce silver solution to metallic silver after being exposed to the stain that contains a reductant, for example hydroquinone or formalin.
Silver nitrate forms insoluble silver phosphate with phosphate ions. When subjected to a reducing agent, usually hydroquinone, it forms black elementary silver. This is used for study of formation of calcium phosphate particles during bone growth.
Silver staining is used in light microscopy. The metallic silver particles are deposited on sensitised reticulin fibres and are then easily seen in the microscopic preparations.
Silver stain aids in the perception of reticular fibers.

# Use in art
Silver staining is also a technique in traditional stained glass to produce the yellow, brown or amber shading when painting on glass. It is a technique that is often used for realistic hair colors. It was discovered in the 14th Century but was not originally used very frequently.
Simple stain
The simple stain is a cell staining technique used in microbiology to colorize cells of microbes.

# Background
Cells are normally translucent or transparent, so without colorization of the cells with a staining method, it would be difficult to see the cells if viewed using a common light microscope.

# Technique
In the simple stain technique or method, a small quantity of cells from a microbial culture or cell growth source is dispersed onto a single drop of water on a clean glass slide and allowed to air dry for 5-10 minutes or until all liquid has evaporated.
The slide is then briefly passed over a flame source (cell source facing upward)--this is called heat fixation, and helps the cells to better adhere to the glass. A dye (stain) solution such as crystal violet, safranin, or a similar dye is flooded onto the surface to cover the cells and allowed to bathe the cells for a minute or two before being rinsed or washed off. These dyes work well on bacteria because they have color-bearing ions (chromophores) that are positively charged (cationic). The slide is allowed to dry, and can then be viewed with a light or brightfield optical microscope so that the cells can be observed and studied.
Ski sickness
Ski sickness is a form of motion sickness suffered by some skiers when weather conditions are bad. Poor visibility in heavy fog can bring on the condition. Symptoms are similar to other sicknesses brought on by motion, namely dizziness, headaches and nausea and in more extreme cases vomiting.
In these whiteout conditions the brain is unable to accurately determine orientation or movement. The condition is caused by the rhythmic turning motion of skiing and other effects such as a reduction in sensory feedback from constrained feet.
Rudolf Hausler of the University of Berne thinks that ski sickness could affect up to 10% of skiers.
Professor Hausler found that over-the-counter prescription medicines for motion sickness relieved the symptoms for most sufferers.
Social mania
Social manias are mass movements which periodically sweep through society, sometimes on a world wide basis. They are characterized by an outpouring of enthusiasm, mass involvement and millennialist goals.  Social manias are contagious social epidemics.  As social phenomena the must be differentiated from mania in individuals, the general state of frenzy, which is a defined psychiatric disease.
Social manias come in different sizes and strengths.  Some social manias fail to 'catch fire', while others persist for hundreds of years (although sometimes in severely attenuated form). Common to all is a vision of salvation, a new way of life, which if realized would radically change everyday life, ushering in a new world of freedom and justice.

# Examples
In recent history, social manias have included Nazism and Communism, including such related phenomena as the Cultural Revolution, McCarthyism; Abolitionism;the Hippies, the Taiping Rebellion; the French Revolution and the current wave of religious fundamentalism, including Islamism, Christian Fundamentalism and Hindu fundamentalism.
The Taiping Rebellion is an excellent illustration, as it was both widespread and destructive and has no modern adherents to whom its use as an example would be a distraction. The Ghost dance which was briefly embraced by Native Americans of the Great Plains in 1890 is another excellent example which may be viewed in some historical perspective, as may The Crusades.

# Assessment
If social manias are to be considered as evil, it is evil that arises from a vision of the good. However, it is a good in competition with other goods, thus implying and resulting in conflict, sometimes very serious conflict resulting in the death of tens of millions of people.

# Further reading
- Jessica Stern, Terror in the Name of God: Why Religious Militants Kill, Harpercollins, August, 2003, hardcover, 400 pages, ISBN 0-06-050532-X
Sodium oxide
Sodium oxide is a chemical compound with the formula Na2O.  It is used in ceramics and glasses. Treatment with water affords sodium hydroxide.
The alkali metal oxides M2O (M = Na, K, Rb) crystallise in the antifluorite structure.  In this motif the positions of the anions and cations are reversed relative to their positions in CaF2.

# Applications
In the typical application, glass contains around 15% sodium oxide, the other components being silicon dioxide and calcium oxide at around 70% and 9%, respectively. The soda serves as a flux to lower the temperature at which the silica melts.  Soda glass has a lower melting temperature vs pure silica, and has improved mechanical properties due to its slight increases in elasticity.  These changes arise because the silicon dioxide and soda react to form sodium silicates of the general formula Na2x.
Na2O forms when sodium is treated with oxygen.
Burning sodium in air will produce Na2O and about 20% sodium peroxide Na2O2.
Pure Na2O can be prepared by reaction of liquid sodium with NaNO3.
Solvent drag
Solvent drag is a phenomenon in renal physiology. It is when solvents in the ultrafiltrate are transported back from the renal tubule by the flow of water rather than specifically by ion pumps or other membrane transport proteins.
It generally occurs in the paracellular, rather than transcellular, pathway across the tubule cells.
It is seen e.g. in the passive transport in renal sodium reabsorption, renal chloride reabsorption as well as renal urea handling.
Somatic cell
A somatic cell is generally taken to mean any cell forming the body of an organism: the word "somatic" is derived from the Greek word soma (), meaning "body". Somatic cells, by definition, are not germline cells. In mammals, germline cells are the spermatozoa and ova (also known as "gametes") which fuse during fertilization to produce a cell called a zygote, from which the entire mammalian embryo develops. Every other cell type in the mammalian bodyapart from the sperm and ova, the cells from which they are made (gametocytes) and undifferentiated stem cellsis a somatic cell:  internal organs, skin, bones, blood, and connective tissue are all made up of somatic cells.

# Genetics and chromosome content
A simple definition of a somatic cell is that it is a non-sex cell (a very broad and not always accurate description). In humans, somatic cells contain 46 individual chromosomes, organised into 23 pairs of chromosomes. Each pair comprises a chromosome inherited from the father and the mother. Human somatic cells contain twice as many chromosomes as germline cells (sex cells). Germline cells contain only 23 chromosomes. When the germline cells meet during conception, they "fuse" together, creating a zygote. The sex of the child is dependent on the chromosome the germline cells contains (X or Y). Due to the "fusion" of the germline cells, a zygote contains 46 chromosomes (i.e. 23 pairs).
In other species, the situation is more complex. Humans, and other species whose somatic cells contain chromosomes arranged in pairs, are known as "diploid" organisms  (their germline cells, which contain only single unpaired chromosomes, are known as "haploid"). However, a large number of species arrange the chromosomes in their somatic cells in fours ("tetraploid") or even sixes ("hexaploid") which means that they can have diploid or even triploid germline cells. An example of this is the modern cultivated species of wheat, Triticum Aestivum L., a hexaploid species whose somatic cells contain six copies of every chromosome.
Somatization

# Overview
Somatization is currently defined as "a tendency to experience and communicate somatic distress in response to psychosocial stress and to seek medical help for it".
This can be, but not always, related to a psychological condition such as:
- Affective disorders (anxiety and depression)
- Somatoform disorders
The American Psychiatric Association (APA) have classified somatoform disorders in the DSM-IV
and the World Health Organization (WHO) have classified these in the ICD-10.
Both classification systems use similar criteria, though due to limited medical knowledge in psychiatric medicine, differences of opinion are expected. Most current practitioners will use one over the other, though in cases of borderline diagnoses, both may be referred to.
Spermatocyte
A spermatocyte is a male gametocyte which is derived from a spermatogonium. Initially in spermatogenesis, a spermatogonium divides by mitosis into two so-called primary spermatocytes. A primary spermatocyte is also diploid, and, in turn, gives place by meiosis to two secondary spermatocytes, which this time are haploid.

# Additional images
- Histological section through testicular parenchyma of a boar. 1 Lumen of Tubulus seminiferus contortus, 2 spermatids, 3 spermatocytes, 4 spermatogonia, 5 Sertoli cell, 6 Myofibroblasts, 7 Leydig cells, 8 capillaries
Histological section through testicular parenchyma of a boar. 1 Lumen of Tubulus seminiferus contortus, 2 spermatids, 3 spermatocytes, 4 spermatogonia, 5 Sertoli cell, 6 Myofibroblasts, 7 Leydig cells, 8 capillaries
Spinal tumor

# Overview
Spinal tumors are neoplasms located in the spinal cord.  They are mostly metastases from primary cancers elsewhere (commonly breast, prostate and lung cancer). Primary tumors may be benign (e.g. hemangioma) or malignant in nature.
Depending on their location, the spinal cord tumors can be:
- Extradural - outside the dura mater lining
- Intradural - part of the dura
- Intramedullary - inside the spinal cord
The symptoms seen are due to spinal nerve compression and weakening of the vertebral structure. Incontinence and decreased sensitivity in the saddle area (buttocks) are generally considered warning signs of spinal cord compression by the tumor. Back pain in a patient with known malignancy may prompt a bone scan to confirm or exclude spinal metastasis.

# Diagnosis
MRI and bone scanning are used for diagnostic purposes. This assesses not only the location of the tumor(s) but also their relationship with the spinal cord and the risk of cord compression.

# Treatment
- Steroids may be administered if there is evidence of spinal cord compression. These do not affect the tumoral mass itself, but tend to reduce the inflammatory reaction around it, and thus decrease the overall volume of the mass impinging on the spinal cord.
- Radiotherapy
- Surgery is sometimes possible
Spinal shock

# Overview
Spinal shock was first defined by Whytt in 1750 as a loss of sensation accompanied by motor paralysis with initial loss but gradual recovery of reflexes, following a spinal cord injury (SCI) -- most often a complete transection. Reflexes in the spinal cord caudal to the SCI are depressed (dysreflexia) or absent (areflexia), while those rostral to the SCI remain unaffected. Note that the 'shock' in spinal shock does not refer to circulatory collapse.

# Phases of Spinal Shock

## Explanation of Phases
Ditunno proposed a four-phase model for spinal shock in 2004.
Phase 1 is characterized by a complete loss -- or weakening -- of all reflexes below the SCI. This phase lasts for a day. The neurons involved in various reflex arcs normally receive a basal level of excitatory stimulation from the brain. After an SCI, these cells lose this input, and the neurons involved become hyperpolarized and therefore less responsive to stimuli.
Phase 2 occurs over the next two days, and is characterized by the return of some, but not all, reflexes below the SCI. The first reflexes to reappear are polysynaptic in nature, such as the bulbocavernosus reflex. Monosynaptic reflexes, such as the deep tendon reflexes, are not restored until Phase 3. Note that restoration of reflexes is not rostral to caudal as previously (and commonly) believed, but instead proceeds from polysynaptic to monosynaptic. The reason reflexes return is the hypersensitivity of reflex muscles following denervation -- more receptors for neurotransmitters are expressed and are therefore easier to stimulate.
Phases 3 and 4 are characterized by hyperreflexia, or abnormally strong reflexes usually produced with minimal stimulation. Interneurons and lower motor neurons below the SCI begin sprouting, attempting to re-establish synapses. The first synapses to form are from shorter axons, usually from interneurons; this is Phase 3. Phase 4, on the other hand, is soma-mediated, and as it takes longer for axonal transport to push growth factors and proteins from soma to the end of the axon, it takes longer.

# Autonomic Effects
In spinal cord injuries above T6, autonomic dysreflexia may occur, from the loss of autonomic innervation from the brain. Sacral parasympathetics (S2-S4) are lost, as are many sympathetic levels, depending on the level of the SCI. Cervical lesions cause total loss of sympathetic innervation and lead to vasovagal hypotension and bradyarrythmias -- which resolve in 3-6 weeks. Autonomic dysreflexia is permanent, and occurs from Phase 4 onwards. It is characterized by unchecked sympathetic stimulation below the SCI (from a loss of cranial regulation), leading to oftentimes extreme hypertension, loss of bladder/bowel control, sweating, headaches, and other sympathetic effects.

# Reference
- Ditunno JF, Little JW, Tessler A, Burns AS. Spinal shock revisited: a four-phase model. Spinal Cord. 2004 Jul;42(7):383-95.
Spinal veins
The veins of the medulla spinalis (spinal veins, veins of the spinal cord) are situated in the pia mater and form a minute, tortuous, venous plexus.
They emerge chiefly from the median fissures of the medulla spinalis and are largest in the lumbar region.
In this plexus there are:
- (1) two median longitudinal veins, one in front of the anterior fissure, and the other behind the posterior sulcus of the cord.
- (2) four lateral longitudinal veins which run behind the nerve roots.
They end in the intervertebral veins.
Near the base of the skull they unite, and form two or three small trunks, which communicate with the vertebral veins, and then end in the inferior cerebellar veins, or in the inferior petrosal sinuses.
Spinnbarkeit
Spinnbarkeit is a medical term and refers to the stringy and/or stretchy quality found to varying degrees in mucus, saliva, and similar fluids. The term is used especially with reference to cervical mucus at the time just prior to or during ovulation.
Under the influence of estrogens this mucus becomes abundant, clear, and stretchable, somewhat like egg white. The stretchability of the mucus is termed spinnbarkeit, meaning in German that it has the ability to be spun. Only such mucus appears to be able to be penetrated by sperm. After ovulation, the character of cervical mucus changes, and under the influence of progesterone it becomes thick, scant, and tacky. Sperm typically cannot penetrate it.
Saliva does not always exhibit spinnbarkeit, but it can under certain circumstances. The thickness and spinnbarkeit of nasal mucus are factors in whether or not the nose seems to be blocked.

# External link
- Natural Family Planning Instructions: Cervical Mucus Method - mjbovo.com.
Splenic cyst

# Overview
Splenic cyst is developmental in origin.
True nonparasitic splenic cyst, also called congenital cyst and epidermoid cyst, is defined by the presence of an inner endotheial lining.

# Differentiating Splenic cyst from Other Diseases
- Inflammatory (abscesses, hydatid cyst)
- Vascular (infarction], peliosis)
- Posttraumatic (hematoma, false cyst)
- Neoplastic (hemangioma, lymphangioma, lymphoma, metastasis)

# Diagnosis

## Ultrasound
- Anechoic well-defined, round mass.

## CT
- CT typically shows a large, low-attenuation,unilocular mass with imperceptible walls;
- HU are in the range of that of water.
- No enhancement is seen after the administration of contrast material

## MRI
- Magnetic resonance (MR) images show a well-defined, round mass.
- On T2-weighted images, the mass has markedly high signal intensity, a characteristic finding of a cyst.
Spoon theory
The Spoon Theory was developed by Christine Miserandino, a lupus sufferer from New York and founder of the website "But You Don't Look Sick."  Miserandino was searching for a way to illustrate to her best friend what she endures every day in order to function with a chronic illness.
The theory uses spoons as units of measurement for personal energy, with the idea being that once the patient has depleted their supply of spoons for the day, they are too exhausted to continue with the necessities of life.
The creation of the theory led to the founding of ButYouDontLookSick.com and remains the single most widely-read article on the website today.
Miserandino went on from the creation of the Spoon Theory to found the website and continue her work as a writer and patient advocate.  In 2008 she and her family will be honored by the Lupus Alliance of America for their ongoing efforts to assist the chronically ill.
Sports drink
A sports drink is a beverage designed to help athletes rehydrate, as well as replenish electrolytes, sugar, and other nutrients, which can be depleted after strenuous training or competition.  Companies marketing these products point out the fact that plain water, despite its association with good health, can actually be toxic if consumed in large amounts (cf. water intoxication).  This can happen because overconsumption of water reduces levels of electrolytes such as sodium and potassium in the body by dilution, interfering with the nervous system. An example of a sport drink is Powerade, or what is possibly the best known sports drink in the United States, Gatorade, which was introduced in 1966.
Currently the largest growing segment of the sports drink market is non-athletes.
This market shift has led some sports drinks manufacturers to specifically target and develop products aimed at non-athletes, such as low-sodium or low-calorie sports drinks. Non-athletes who use sports drinks should also be aware that sports drinks for athletes typically contain high levels of carbohydrates which will result in weight gain if consumed without a corresponding increase in exercise activity.
Sports drinks are not to be confused with energy drinks (e.g. Full Throttle, Lucozade, Mountain Dew AMP, or Monster Energy). Sports drinks are intended to replenish electrolytes, sugar, water, and other nutrients, and are usually isotonic (containing the same proportions as found in the human body).  Energy drinks, on the other hand, simply provide lots of sugar and caffeine.
The sports drinks on the market today include Gatorade by PepsiCo, Inc., All Sport by Monarch Beverage Co., Powerade by Coca Cola, Accelerade by PacificHealth Laboratories, Lucozade Sport by GlaxoSmithKline, Cera Sport by Cera Products, and many others such as Pocari Sweat.
Stage fright

# Background
Stage fright or performance anxiety refers to an anxiety, fear or persistent phobia related to performance in front of an audience or camera. This form of anxiety can precede or accompany participation in any activity involving public self-presentation.

# Explanation
Often the term "stage fright" or topophobia is conflated with glossophobia, a fear of speaking in public.  Jugglers and mimes are the simplest examples of the difference in notions.
Performance anxiety is also observed in sportsmen. In the latter case it is interpreted as a fear to underperform (in view of the actual public or implied publicity).
Quite often stage fright arises in a mere anticipation of a performance, often long time ahead. It has numerous manifestations: fluttering or pounding heart, tremor in hands and legs, diarrhea, facial nerve tics, dry mouth.
Stage fright may be observed in ordinary people, beginning artists, as well as in accomplished ones.
Some musicians use beta blockers to avoid stage fright during auditions, and performances. In other cases, performers use alcoholic beverages to ease their stage fright. There have been many cases in which this habit has led to alcoholism.

# Footnotes
-  Better Playing Through Chemistry by Blair Tindall, New York Times October 17, 2004.
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