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Equalisation (diving)
Ear clearing, clearing the ears or equalization is any of various maneuvers to equalize the pressure in the middle ear with the outside pressure, by letting air enter along the Eustachian tubes, as this does not always happen automatically when the pressure in the middle ear is lower than the outside pressure. This need can arise in scuba diving, freediving/spearfishing, skydiving, fast descent in an aircraft, fast descent in a mine cage, and being put into pressure in a caisson or similar internally pressurised enclosure, or sometimes even simply travelling at fast speeds in an automobile. Normally the ears will clear automatically during a reduction in ambient pressure, but if they do not, a reverse squeeze may occur, which can also require clearing to avoid causing injury to the eardrum or inner ear. People who do intense weight lifting, such as squats, may experience sudden conductive hearing loss due to air pressure building up inside the ear. An ear clearing maneuver wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Politzerization
Politzerization, also called the Politzer maneuver or method, is a medical procedure that involves inflating the middle ear by blowing air up the nose during the act of swallowing. It is often performed to reopen the Eustachian tube and equalise pressure in the middle ear. The procedure was derived from a medical experiment first performed by Ádám Politzer of Vienna that involved studying the air movement through the Eustachian tube by connecting a manometer to the external auditory canal meatus and another manometer in the pharynx. His first results on the technique were published in 1861 and he introduced a pear-shaped rubber air-bag for performing the procedure in 1863, which came to be known as a Politzer bag. This system was far more practical and less difficult for the patient than catheterizing the Eustachian tube and brought fame to Politzer. Use in clinical devices One device that utilizes Politzeration is the EarPopper, developed by Shlomo Silman, Ph.D., profes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Cold
The common cold, or the cold, is a virus, viral infectious disease of the upper respiratory tract that primarily affects the Respiratory epithelium, respiratory mucosa of the human nose, nose, throat, Paranasal sinuses, sinuses, and larynx. Signs and symptoms may appear in as little as two days after exposure to the virus. These may include coughing, sore throat, rhinorrhea, runny nose, Sneeze, sneezing, headache, fatigue, and fever. People usually recover in seven to ten days, but some symptoms may last up to three weeks. Occasionally, those with other health problems may develop pneumonia. Well over 200 virus strains are implicated in causing the common cold, with rhinoviruses, coronaviruses, Adenoviridae, adenoviruses and enteroviruses being the most common. They spread through the air or indirectly through contact with objects in the environment, followed by transfer to the mouth or nose. Risk factors include going to child care facilities, Sleep deprivation, not sleepin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diving Suit
A diving suit is a garment or device designed to protect a diver from the underwater environment. A diving suit may also incorporate a breathing gas supply (such as for a standard diving dress or atmospheric diving suit), but in most cases the term applies only to the environmental protective covering worn by the diver. The breathing gas supply is usually referred to separately. There is no generic term for the combination of suit and breathing apparatus alone. It is generally referred to as diving equipment or dive gear along with any other equipment necessary for the dive. Diving suits can be divided into two classes: "soft" or ambient pressure diving suits – examples are wetsuits, dry suits, semi-dry suits and dive skins – and "hard" or atmospheric pressure diving suits, armored suits that keep the diver at atmospheric pressure at any depth within the operating range of the suit. Hot water suits are actively heated wetsuits. Function The diving suit is worn as pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinus (anatomy)
A sinus is a sac or cavity in any organ or tissue, or an abnormal cavity or passage. In common usage, "sinus" usually refers to the paranasal sinuses, which are air cavities in the cranial bones, especially those near the nose and connecting to it. Most individuals have four paired cavities located in the cranial bone or skull. Etymology ''Sinus'' is Latin for "bay", "pocket", "curve", or "bosom". In anatomy, the term is used in various contexts. The word "sinusitis" is used to indicate that one or more of the membrane linings found in the sinus cavities has become inflamed or infected. It is however distinct from a fistula, which is a tract connecting two epithelial surfaces. If left untreated, infections occurring in the sinus cavities can affect the chest and lungs. Sinuses in the body * Paranasal sinuses ** Maxillary ** Ethmoid ** Sphenoid ** Frontal * Dural venous sinuses ** Anterior midline *** Cavernous *** Superior petrosal *** Inferior petrosal ** Central sul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paranasal Sinus
Paranasal sinuses are a group of four paired skeletal pneumaticity, air-filled spaces that surround the nasal cavity. The maxillary sinuses are located under the eyes; the frontal sinuses are above the eyes; the Ethmoid sinus, ethmoidal sinuses are between the eyes and the sphenoidal sinuses are behind the eyes. The sinus (anatomy), sinuses are named for the Facial skeleton, facial bones and sphenoid bone in which they are located. Their role is disputed. Structure Humans possess four pairs of paranasal sinuses, divided into subgroups that are named according to the bones within which the sinuses lie. They are all innervated by branches of the trigeminal nerve (CN V). * The maxillary sinuses, the largest of the paranasal sinuses, are under the Human eye, eyes, in the maxillary bones (open in the back of the semilunar hiatus of the nose). They are innervated by the maxillary nerve (CN V2). * The frontal sinuses, superior to the eyes, in the frontal bone, which forms the hard part o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertigo (medical)
Vertigo is a condition in which a person has the sensation that they are moving, or that objects around them are moving, when they are not. Often it feels like a spinning or swaying movement. It may be associated with nausea, vomiting, perspiration, or difficulties walking. It is typically worse when the head is moved. Vertigo is the most common type of dizziness. The most common disorders that result in vertigo are benign paroxysmal positional vertigo (BPPV), Ménière's disease, and vestibular neuritis. Less common causes include stroke, brain tumors, brain injury, multiple sclerosis, migraines, trauma, and uneven pressures between the middle ears. Physiologic vertigo may occur following being exposed to motion for a prolonged period such as when on a ship or simply following spinning with the eyes closed. Other causes may include toxin exposures such as to carbon monoxide, alcohol, or aspirin. Vertigo typically indicates a problem in a part of the vestibular system. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inner Ear
The inner ear (internal ear, auris interna) is the innermost part of the vertebrate ear. In vertebrates, the inner ear is mainly responsible for sound detection and balance. In mammals, it consists of the bony labyrinth, a hollow cavity in the temporal bone of the skull with a system of passages comprising two main functional parts: * The cochlea, dedicated to hearing; converting sound pressure patterns from the outer ear into electrochemical impulses which are passed on to the brain via the auditory nerve. * The vestibular system, dedicated to balance (ability), balance. The inner ear is found in all vertebrates, with substantial variations in form and function. The inner ear is innervated by the eighth cranial nerve in all vertebrates. Structure The labyrinth can be divided by layer or by region. Bony and membranous labyrinths The bony labyrinth, or osseous labyrinth, is the network of passages with bony walls lined with periosteum. The three major parts of the bony labyrin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eardrum
In the anatomy of humans and various other tetrapods, the eardrum, also called the tympanic membrane or myringa, is a thin, cone-shaped membrane that separates the external ear from the middle ear. Its function is to transmit changes in pressure of sound from the air to the ossicles inside the middle ear, and thence to the oval window in the fluid-filled cochlea. The ear thereby converts and amplifies vibration in the air to vibration in cochlear fluid. The malleus bone bridges the gap between the eardrum and the other ossicles. Rupture or perforation of the eardrum can lead to conductive hearing loss. Collapse or retraction of the eardrum can cause conductive hearing loss or cholesteatoma. Structure Orientation and relations The tympanic membrane is oriented obliquely in the anteroposterior, mediolateral, and superoinferior planes. Consequently, its superoposterior end lies lateral to its anteroinferior end. Anatomically, it relates superiorly to the middle crani ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Training
Training is teaching, or developing in oneself or others, any skills and knowledge or fitness that relate to specific useful competencies. Training has specific goals of improving one's capability, capacity, productivity and performance. It forms the core of apprenticeships and provides the backbone of content at institutes of technology (also known as technical colleges or polytechnics). In addition to the basic training required for a trade, occupation or profession, training may continue beyond initial competence to maintain, upgrade and update skills throughout working life. People within some professions and occupations may refer to this sort of training as professional development. Training also refers to the development of physical fitness related to a specific competence, such as sport, martial arts, military applications and some other occupations. Training methods of all types can be improved by setting specific, time-based, and difficult goals. This allows for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goggles
Goggles, or safety glasses, are forms of protective eyewear that usually enclose or protect the area surrounding the eye in order to prevent particulates, water or chemicals from striking the eyes. They are used in chemistry laboratories and in woodworking. They are often used in snow sports as well, and in the sport of swimming. Goggles are often worn when using power tools such as drills or chainsaws to prevent flying particles from damaging the eyes. Many types of goggles are available as prescription goggles for those with vision problems. History The Inuit and Yupik carved snow goggles from the antlers of caribou, wood, and shell to help prevent snow blindness. The goggles were curved to fit the user's face and had a large groove cut in the back to allow for the nose. A long thin slit was cut through the goggles to allow in a small amount of light, diminishing subsequent ultraviolet rays. The goggles were held to the head by a cord made of caribou sinew. In the ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diving Mask
A diving mask (also half mask, dive mask or scuba mask) is an item of diving equipment that allows Underwater diving, underwater divers, including scuba diving, scuba divers, free-diving, free-divers, and snorkeling, snorkelers, to see clearly underwater. Surface supplied diving, Surface supplied divers usually use a full face mask or diving helmet, but in some systems the half mask may be used. When the human eye is in direct contact with water as opposed to air, its normal environment, light entering the eye is refracted by a different angle and the eye is unable to Focus (optics), focus the light on the retina. By providing an air space in front of the eyes, the eye is able to focus nearly normally. The shape of the air space in the mask slightly affects the ability to focus. Corrective lenses can be fitted to the inside surface of the viewport or contact lenses may be worn inside the mask to allow normal vision for people with focusing defects. When the diver descends, the am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
