A hot spring is a spring produced by the emergence of geothermally heated groundwater that rises from the Earth's crust. While some of these springs contain water, a safe temperature for bathing, others are so hot that immersion can result in an injury or death. There is no universally accepted definition of a hot spring. For example, one can find the phrase hot spring defined as any geothermal spring a spring with water temperatures above its surroundings a natural spring with water temperature above human body temperature a thermal spring with water warmer than 36.7 °C a natural spring of water greater than 21.1 °C a natural discharge of groundwater with elevated temperatures a type of thermal spring in which hot water is brought to the surface. The water temperature of a hot spring is 6.5 °C or more above mean air temperature. Note that by this definition, "thermal spring" is not synonymous with the term "hot spring" a spring whose hot water is brought to the surface; the water temperature of the spring is 8.3 °C or more above the mean air temperature.

A spring with water above average ambient ground temperature. A spring with water temperatures above 50 °C The related term "warm spring" is defined as a spring with water temperature less than a hot spring by many sources, although Pentecost et al. suggest that the phrase "warm spring" is not useful and should be avoided. The US NOAA Geophysical Data Center defines a "warm spring" as a spring with water between 20 and 50 °C. Much of the heat is created by decay of radioactive elements. An estimated 45 to 90 percent of the heat escaping from the Earth originates from radioactive decay of elements located in the mantle; the major heat-producing isotopes in the Earth are potassium-40, uranium-238, uranium-235, thorium-232. Water issuing from a hot spring is heated geothermally, that is, with heat produced from the Earth's mantle. In general, the temperature of rocks within the earth increases with depth; the rate of temperature increase with depth is known as the geothermal gradient. If water percolates enough into the crust, it will be heated as it comes into contact with hot rocks.

The water from hot springs in non-volcanic areas is heated in this manner. In active volcanic zones such as Yellowstone National Park, water may be heated by coming into contact with magma; the high temperature gradient near magma may cause water to be heated enough that it boils or becomes superheated. If the water becomes so hot that it builds steam pressure and erupts in a jet above the surface of the Earth, it is called a geyser. If the water only reaches the surface in the form of steam, it is called a fumarole. If the water is mixed with mud and clay, it is called a mud pot. Note that hot springs in volcanic areas are at or near the boiling point. People have been scalded and killed by accidentally or intentionally entering these springs. Warm springs are sometimes the result of cold springs mixing, they may occur within a volcanic outside of one. One example of a non-volcanic warm spring is Georgia. Hot springs range in flow rate from the tiniest "seeps" to veritable rivers of hot water. Sometimes there is fountain.

There are many claims in the literature about the flow rates of hot springs. There are many more high flow non-thermal springs than geothermal springs. For example, there are 33 recognized "magnitude one springs" (having a flow in excess of 2,800 L/s in Florida alone. Silver Springs, Florida has a flow of more than 21,000 L/s. Springs with high flow rates include: The Excelsior Geyser Crater in Yellowstone National Park yields about 4,000 U. S. gal/min. Evans Plunge in Hot Springs, South Dakota has a flow rate of 5,000 U. S. gal/min of 87 °F spring water. The Plunge, built in 1890, is the world's largest natural warm water indoor swimming pool; the combined flow of the 47 hot springs in Hot Springs, Arkansas is 35 L/s. The hot spring of Saturnia, Italy with around 500 liters a second The combined flow of the hot springs complex in Truth or Consequences, New Mexico is estimated at 99 liters/second. Lava Hot Springs in Idaho has a flow of 130 liters/second. Glenwood Springs in Colorado has a flow of 143 liters/second.

Elizabeth Springs in western Queensland, Australia might have had a flow of 158 liters/second in the late 19th century, but now has a flow of about 5 liters/second. Deildartunguhver in Iceland has a flow of 180 liters/second; the hot springs of Brazil's Caldas Novas are tapped by 86 wells, from which 333 liters/second are pumped for 14 hours per day. This corresponds to a peak average flow rate of 3.89 liters/second per well. The 2,850 hot springs of Beppu in Japan are the highest flow hot spring complex in Japan. Together the Beppu hot springs produce about 1,592 liters/second, or corresponding to an average hot spring flow of 0.56 liters/second. The 303 hot springs of Kokonoe in Japan produce 1,028 liters/second, which gives the average hot spring a flow of 3.39 liters/second. Ōita Prefecture has 4,762 hot springs, with a total flow of 4,437 liters/second, so the average hot spring flow is 0.93 liters/second. The highest flow rate hot spring in Japan is the Tamagawa Hot Spring in Akita Prefecture, which has a flow rate of 150 liters/second.

The Tamagawa Hot Spring feeds a 3 m wide stream with a temperature of 98 °C

Orthostatic headache is a medical condition in which a person develops a headache while vertical and the headache is relieved when horizontal. It was misdiagnosed as different primary headache disorders such as migraine or tension headaches. Increasing awareness of the symptom and its causes missed diagnosis; the most common cause of orthostatic headache is low cerebrospinal fluid pressure, due to a spontaneous cerebrospinal fluid leak, a traumatic cerebrospinal fluid leak, or a post-dural-puncture leak. It is occasionally the most prominent symptom of postural orthostatic tachycardia syndrome. Distinguishing POTS from a cerebrospinal fluid leak can be difficult, because the defining symptom of POTS, positional tachycardia occurs in some people with cerebrospinal fluid leaks. Furthermore, both POTS and cerebrospinal fluid leaks are sometimes present in the same person in people with Ehlers–Danlos syndrome. Other causes include colloid cysts and connective tissue disorders, it may occur as a complication of decompressive surgery for Chiari malformation or decompressive craniectomies for cerebral edema.

Cerebrospinal Fluid Leak causes loss of CSF volume around the brain. This causes the brain to lose its buoyancy, which results in pressure on pain-sensitive areas like the dura and blood vessels; the pain is what results in a headache, because the brain is more reliant on its buoyancy in an upright position the headache can be relieved by switching to a horizontal position. Cerebrospinal fluid leaks are diagnosed by performing different tests. A diagnostic dural puncture is used because its results show the presence of a leak easily. Other types of tests that could be used are cranial CT, cranial MRI, spinal MRI, CT myelography. A cranial MRI can be diagnostic by showing one of the five main findings, which are subdural fluid collections, enhancement of venous structures, pituitary hyperemia, sagging of the brain. Another cause of orthostatic headaches is postural orthostatic tachycardia syndrome, a form of dysautonomia, diagnosed with autonomic testing instead of the imaging tests that are used to determine a CSF leak.

It can be difficult to distinguish if a patient is affected by POTS because patients with CSF leaks have similar symptoms and may develop secondary POTS. Cerebrospinal Fluid leaks can be managed short term with bed rest and lots of hydration, they can be treated with an epidural blood patch with autologous blood, the standard initial procedure. If an EBP is ineffective, surgery is an option for treatment. A surgical procedure would be customized to the patient depending on the location and size of the leak. POTS patients manage their symptoms with medication and preventative behaviors. Drugs such as midodrine, fludrocortisone and pyridostigmine are sometimes prescribed to help stabilize blood pressure. Patients can work with their diet to ensure they are getting the crucial amount of fluid intake and increasing their intake of salt. Both dietary changes can help prevent symptoms from occurring. Water-bolus treatment can help in times of increased orthostatic stress. Patients drink two 8 ounce glasses of cold water which will increased standing blood pressure for a short amount of time.

Most orthostatic headaches have a favorable outcome. POTS patients who manage their symptoms can recognize when their symptoms are occurring and prevent them from affecting their everyday life. CSF leaks are repaired with only about 10% of patients experiencing recurrence. All different types of patients have presented orthostatic headaches as symptoms, it is more prevalent in females, with a female-to-male ratio of 1.5:1. The average age of symptom presentation is around 40 years old. CSF leaks are more common in patients that have connective tissue diseases such as Ehlers-Danlos syndrome

Francisco Javier Bautista, Jr. better known by his stage name Frankie J, is a Mexican-American singer, songwriter and former member of the musical group Kumbia Kings. Born in Mexico, he grew up in San Diego and became a freestyle artist under the stage name Frankie Boy in the late 1990s, he joined Kumbia Kings before re-embarking on a solo career. Frankie J's solo debut album, What's a Man to Do, was released in 2003, followed by more English and Spanish language albums, he received a Grammy Award nomination for his album Faith, Hope y Amor in 2013 for Best Latin Pop Album. Bautista was born in Tijuana and raised in San Diego, California from the age of two, after his uncle brought him and his siblings to the United States, he grew up listening to both traditional Latin music as well as American urban music. He attended Southwest Senior High School in San Diego, he began to develop more interest in singing, with the encouragement of his family. At high school age, he began performing at school functions.

In 1997, Bautista signed with the now defunct Hola Recordings which at the time had only one artist signed to the label, the brainchild of dance music legend and producer Jellybean Benitez. At the time, he was a freestyle artist known as Frankie Boy and his music was released on 3 Maximum Freestyle compilations but his solo CD was shelved before release. In 1999 he became a member of the Kumbia Kings created by A. B. Quintanilla, brother of Selena, he performed under Cisko. Frankie J signed as a solo artist with Columbia Records and released his first album What's A Man To Do on May 27, 2003, his self-titled first Spanish-language album Frankie J was released in the same year. The album's lead single "Don't Wanna Try" peaked at #19 on the Billboard Hot 100 Singles Chart, while "Ya No Es Igual" went Top 10 on the World Latin charts; that year, he was featured in the Top 10 Billboard Hot 100 hit "Suga Suga" by rapper Baby Bash. His second album The One was released on March 22, 2005, it was led by the #3 Billboard Hot 100 hit "Obsession" featuring rapper Baby Bash, followed by the Top40 singles "How To Deal" and "More Than Words".

To coincide with the release of "More Than Words", the album was re-released on the DualDisc format in October. By January 2006, The One was certified platinum by the RIAA for shipping over a million copies, his second Spanish-language album Un Nuevo Dia was released on June 13, 2006, featured the single "Pensado En Ti". Frankie's third English-language album, was released on October 17, 2006, it debuted at #30 on the Billboard 200. The lead single "That Girl" featured Chamillionaire and Mannie Fresh and peaked at number 43 on the Billboard Hot 100. A second single, "Daddy's Little Girl", charted at number 23 on the Billboard Bubbling Under Hot 100 chart. Following his departure from Columbia Records, Frankie J released a few singles between 2008 and 2011, as well as starting his own label, Soulsick Records, he has written songs for other artists, most the number 2 hit song "Take a Chance on Me" in the United Kingdom for boyband JLS. He released his fourth English-language studio album Courage on December 7, 2011.

The lead single "How Beautiful You Are" was released to digital retailers on October 24, 2011. The music video was directed by Mike Ho and premiered on YouTube on September 11, 2011; the video for the album's second single "And I Had You There" premiered on Frankie's YouTube channel on November 26, 2011. Frankie J and Baby Bash shot a video for the album's third single "That's Wussup" in December 2011 in San Diego, California; the video premiered on January 8, 2012. On July 12, 2012, it was announced that Frankie J will join Jennifer Lopez and Enrique Iglesias on their joint North America tour, serving as a special guest, replacing Wisin & Yandel who were the opening act. In 2011 he began work on a new Spanish-language album, he released two digital singles in late 2012. In 2013, he released his new album, Hope y Amor on May 28, 2013; the album was nominated for the 56th annual Grammy Award under the category of Best Latin Pop Album. It was preceded by the release of the singles "No Te Quiero Ver Con Él" and "Beautiful".

"Impossible" was released as a single. On November 26, 2015, he premiered the single "Breakin'", with a music video premiering on December 14; the digital single was released on December 25, 2015. Four additional singles — "Let the Music Take Control", "I Promise You", "Riches in Heaven", "Body Rock" — followed in 2016, he announced. Another single "Not So Dangerous" was released on December 25, 2016. In March 2017, he scored a radio hit with "Si Una Vez", a collaboration with Play-N-Skillz and Leslie Grace. In June, he collaborated with Baby Bash for a new single titled "Vamonos." The following month in July, he released a new single "Lowrider" with Baby Bash, C Kan, Ozomatli & Kid Frost. On July 27, he released his new studio album titled Eleven through his own label Soulsick Musick Inc. Frankie appeared as a celebrity guest at the 16th birthday party of Marissa Mishelle on MTV's My Super Sweet 16. In 2011, he joined the mun2 television series RPM Miami as mechanic Ramon; the series was renewed for a second season.

A Performed in Spanish Official Facebook Page Frankie J on IMDb