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68-404: All people with Holt-Oram syndrome have at least one abnormal wrist bone , which can often only be detected by X-ray . Other bone abnormalities are associated with the syndrome. These vary widely in severity, and include a missing thumb, a thumb that looks like a finger , upper arm bones of unequal length or underdeveloped, partial or complete absence of bones in the forearm, and abnormalities in

136-442: A dorsopalmar axis running through the head of the capitate bone. During palmar flexion the proximal carpal bones are displaced towards the dorsal side and towards the palmar side during dorsiflexion . While flexion and extension consist of movements around a pair of transverse axes — passing through the lunate bone for the proximal row and through the capitate bone for the distal row — palmar flexion occurs mainly in

204-413: A layer of compact bone . Occasionally accessory bones are found in the carpus, but of more than 20 such described bones, only four (the central, styloid, secondary trapezoid, and secondary pisiform bones) are considered to be proven accessory bones. Sometimes the scaphoid, triquetrum, and pisiform bones are divided into two. The carpal bones are ossified endochondrally (from within the cartilage) and

272-404: A man's foot length was 26.3 cm with a standard deviation of 1.2 cm. The foot can be subdivided into the hindfoot, the midfoot, and the forefoot: The hindfoot is composed of the talus (or ankle bone) and the calcaneus (or heel bone). The two long bones of the lower leg, the tibia and fibula , are connected to the top of the talus to form the ankle . Connected to the talus at

340-412: A transverse arch maintained by the interlocking shapes of the foot bones, strong ligaments, and pulling muscles during activity. The slight mobility of these arches when weight is applied to and removed from the foot makes walking and running more economical in terms of energy. As can be examined in a footprint, the medial longitudinal arch curves above the ground. This arch stretches from the heel bone over

408-439: Is an instance of i-mutation. The human foot is a strong and complex mechanical structure containing 26 bones , 33 joints (20 of which are actively articulated), and more than a hundred muscles , tendons , and ligaments . The joints of the foot are the ankle and subtalar joint and the interphalangeal joints of the foot . An anthropometric study of 1197 North American adult Caucasian males (mean age 35.5 years) found that

476-462: Is formed by the triceps surae and the plantaris . The triceps surae consists of the soleus and the two heads of the gastrocnemius . The heads of gastrocnemius arise on the femur , proximal to the condyles, and the soleus arises on the proximal dorsal parts of the tibia and fibula. The tendons of these muscles merge to be inserted onto the calcaneus as the Achilles tendon . The plantaris originates on

544-500: Is never found in amphibians. Because many tetrapods have fewer than five digits on the forelimb, even greater degrees of fusion are common, and a huge array of different possible combinations are found. The wing of a modern bird , for example, has only two remaining carpals; the radiale (the scaphoid of mammals) and a bone formed from the fusion of four of the distal carpals. The carpus and tarsus are both described as podial elements or (clusters of) podial bones. In some macropods ,

612-399: Is the most common sexual fetish. A paw is the soft foot of a mammal, generally a quadruped, that has claws or nails (e.g., a cat or dog's paw). A hard foot is called a hoof . Depending on style of locomotion, animals can be classified as plantigrade (sole walking), digitigrade (toe walking), or unguligrade (nail walking). The metatarsals are the bones that make up the main part of

680-651: Is the terminal portion of a limb which bears weight and allows locomotion . In many animals with feet, the foot is a separate organ at the terminal part of the leg made up of one or more segments or bones, generally including claws and/or nails. The word "foot", in the sense of meaning the "terminal part of the leg of a vertebrate animal" comes from Old English fot , from Proto-Germanic * fot (source also of Old Frisian fot , Old Saxon fot , Old Norse fotr , Danish fod , Swedish fot , Dutch voet , Old High German fuoz , German Fuß , Gothic fotus , all meaning "foot"), from PIE root * ped- "foot". The plural form feet

748-420: Is the way that the body naturally absorbs shock. Neutral pronation is the most ideal, efficient type of gait when using a heel strike gait; in a forefoot strike, the body absorbs shock instead via flexion of the foot. As with a neutral pronator, an individual who overpronates initially strikes the ground on the lateral side of the heel. As the individual transfers weight from the heel to the metatarsus, however,

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816-422: Is useful in forensic age estimation. There are four groups of ligaments in the region of the wrist: The hand is said to be in straight position when the third finger runs over the capitate bone and is in a straight line with the forearm. This should not be confused with the midposition of the hand which corresponds to an ulnar deviation of 12 degrees. From the straight position two pairs of movements of

884-460: The TBX5 gene cause Holt–Oram syndrome. The TBX5 gene produces a protein that is critical for the proper development of the heart and upper limbs before birth. Holt–Oram syndrome has an autosomal dominant pattern of inheritance, meaning one abnormal copy of the gene is sufficient to cause disease, which each child has a 50% chance of inheriting from an affected parent. However, in 85 percent of cases,

952-416: The collar bone or shoulder blade . Bone abnormalities may affect only one side of the body or both sides; if both sides are affected differently, the left side is usually affected more severely. About 75 percent of individuals with Holt–Oram syndrome also have congenital heart problems, with the most common being defects in the tissue wall between the upper chambers of the heart ( atrial septal defect ) or

1020-423: The dorsum (the area facing upward while standing) and the planum (the area facing downward while standing). The instep is the arched part of the top of the foot between the toes and the ankle. There can be many sesamoid bones near the metatarsophalangeal joints, although they are only regularly present in the distal portion of the first metatarsal bone . The human foot has two longitudinal arches and

1088-406: The flexor retinaculum . The proximal row comprises the scaphoid , lunate , triquetral , and pisiform bones which articulate with the surfaces of the radius and distal carpal row, and thus constantly adapts to these mobile surfaces. Within the proximal row, each carpal bone has slight independent mobility. For example, the scaphoid contributes to midcarpal stability by articulating distally with

1156-408: The foot is the tarsus . The carpal bones allow the wrist to move and rotate vertically. The eight carpal bones may be conceptually organized as either two transverse rows, or three longitudinal columns. When considered as paired rows, each row forms an arch which is convex proximally and concave distally. On the palmar side, the carpus is concave and forms the carpal tunnel , which is covered by

1224-406: The radiale , intermedium , and ulnare , after their proximal articulations, and are homologous with the scaphoid, lunate, and triquetral bones respectively. The remaining bones are simply numbered, as the first to fourth centralia (singular: centrale ), and the first to fifth distal carpals . Primitively, each of the distal bones appears to have articulated with a single metacarpal. However,

1292-549: The radiocarpal joint and dorsiflexion in the midcarpal joint . Dorsiflexion is produced by (in order of importance) extensor digitorum , extensor carpi radialis longus , extensor carpi radialis brevis , extensor indicis , extensor pollicis longus , and extensor digiti minimi . Palmar flexion is produced by (in order of importance) flexor digitorum superficialis , flexor digitorum profundus , flexor carpi ulnaris , flexor pollicis longus , flexor carpi radialis , and abductor pollicis longus . Combined with movements in both

1360-442: The sole of foot , those of the first and last digits, and a central group: Muscles of the big toe : the abductor hallucis stretches medially along the border of the sole, from the calcaneus to the first digit. Below its tendon, the tendons of the long flexors pass through the tarsal canal . The abductor hallucis is an abductor and a weak flexor, and also helps maintain the arch of the foot. The flexor hallucis brevis arises on

1428-412: The subtalar joint , the calcaneus, the largest bone of the foot, is cushioned underneath by a layer of fat. The five irregular bones of the midfoot , the cuboid , navicular , and three cuneiform bones, form the arches of the foot which serve as a shock absorber. The midfoot is connected to the hind- and fore-foot by muscles and the plantar fascia . The forefoot is composed of five toes and

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1496-425: The "keystone" ankle bone to the three medial metatarsals. In contrast, the lateral longitudinal arch is very low. With the cuboid serving as its keystone, it redistributes part of the weight to the calcaneus and the distal end of the fifth metatarsal. The two longitudinal arches serve as pillars for the transverse arch which run obliquely across the tarsometatarsal joints. Excessive strain on the tendons and ligaments of

1564-458: The back of the hand, so called dorsiflexion) is possible with a total range of 170 degrees. During radial abduction the scaphoid is tilted towards the palmar side which allows the trapezium and trapezoid to approach the radius. Because the trapezoid is rigidly attached to the second metacarpal bone to which also the flexor carpi radialis and extensor carpi radialis are attached, radial abduction effectively pulls this combined structure towards

1632-402: The calcaneus to the proximal phalanx of the fifth digit, the abductor digiti minimi form the lateral margin of the foot and are the largest of the muscles of the fifth digit. Arising from the base of the fifth metatarsal, the flexor digiti minimi is inserted together with abductor on the first phalanx. Often absent, the opponens digiti minimi originates near the cuboid bone and is inserted on

1700-407: The calf. The flexor hallucis longus arises on the back of the fibula on the lateral side, and its relatively thick muscle belly extends distally down to the flexor retinaculum where it passes over to the medial side to stretch across the sole to the distal phalanx of the first digit. The popliteus is also part of this group, but, with its oblique course across the back of the knee, does not act on

1768-401: The central part of the midfoot, and the transverse head originating near the metatarsophalangeal joints of digits five to three. Both heads are inserted into the lateral sesamoid bone of the first digit. The adductor hallucis acts as a tensor of the plantar arches and also adducts the big toe and might plantar flex the proximal phalanx. Muscles of the little toe : Stretching laterally from

1836-432: The corresponding five proximal long bones forming the metatarsus . Similar to the fingers of the hand, the bones of the toes are called phalanges and the big toe has two phalanges while the other four toes have three phalanges each. The joints between the phalanges are called interphalangeal and those between the metatarsus and phalanges are called metatarsophalangeal (MTP). Both the midfoot and forefoot constitute

1904-415: The digits. The extensor hallucis longus originates medially on the fibula and is inserted on the first digit. It dorsiflexes the big toe and also acts on the ankle in the unstressed leg. In the weight-bearing leg, it acts similarly to the tibialis anterior. Peroneal group : the peroneus longus arises on the proximal aspect of the fibula and peroneus brevis below it. Together, their tendons pass behind

1972-410: The dorsal surfaces being the broader, except in the lunate. The superior or proximal, and inferior or distal surfaces are articular, the superior generally convex, the inferior concave; the medial and lateral surfaces are also articular where they are in contact with contiguous bones, otherwise they are rough and tuberculated. The structure in all is similar: cancellous tissue enclosed in

2040-572: The eight small bones that make up the wrist (carpus) that connects the hand to the forearm . The terms "carpus" and "carpal" are derived from the Latin carpus and the Greek καρπός (karpós), meaning "wrist". In human anatomy , the main role of the carpal bones is to articulate with the radial and ulnar heads to form a highly mobile condyloid joint (i.e. wrist joint ), to provide attachments for thenar and hypothenar muscles, and to form part of

2108-413: The elbow and shoulder joints, intermediate or combined movements in the wrist approximate those of a ball-and-socket joint with some necessary restrictions, such as maximum palmar flexion blocking abduction. Anteroposterior gliding movements between adjacent carpal bones or along the midcarpal joint can be achieved by stabilizing individual bones while moving another (i.e. gripping the bone between

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2176-400: The feet can result in fallen arches or flat feet . The muscles acting on the foot can be classified into extrinsic muscles , those originating on the anterior or posterior aspect of the lower leg, and intrinsic muscles , originating on the dorsal (top) or plantar (base) aspects of the foot. All muscles originating on the lower leg except the popliteus muscle are attached to the bones of

2244-460: The femur proximal to the lateral head of the gastrocnemius and its long tendon is embedded medially into the Achilles tendon. The triceps surae is the primary plantar flexor. Its strength becomes most obvious during ballet dancing. It is fully activated only with the knee extended, because the gastrocnemius is shortened during flexion of the knee. During walking it not only lifts the heel, but also flexes

2312-423: The fifth metatarsal bone. These three muscles act to support the arch of the foot and to plantar flex the fifth digit. Central muscle group : The four lumbricals arise on the medial side of the tendons of flexor digitorum longus and are inserted on the medial margins of the proximal phalanges. The quadratus plantae originates with two slips from the lateral and medial margins of the calcaneus and inserts into

2380-423: The foot and lift its medial edge ( supination ). In the weight-bearing leg, it brings the leg toward the back of the foot, like in rapid walking. The extensor digitorum longus arises on the lateral tibial condyle and along the fibula, and is inserted on the second to fifth digits and proximally on the fifth metatarsal. The extensor digitorum longus acts similar to the tibialis anterior except that it also dorsiflexes

2448-399: The foot in humans, and part of the leg in large animals or paw in smaller animals. The number of metatarsals are directly related to the mode of locomotion with many larger animals having their digits reduced to two ( elk , cow , sheep ) or one ( horse ). The metatarsal bones of feet and paws are tightly grouped compared to, most notably, the human hand where the thumb metacarpal diverges from

2516-413: The foot will roll too far in a medial direction, such that the weight is distributed unevenly across the metatarsus, with excessive weight borne on the hallux . In this stage of the gait, the knee will generally, but not always, track inward. An overpronator does not absorb shock efficiently. Imagine someone jumping onto a diving board, but the board is so flimsy that when it is struck, it bends and allows

2584-420: The foot. On the top of the foot, the tendons of extensor digitorum brevis and extensor hallucis brevis lie deep in the system of long extrinsic extensor tendons. They both arise on the calcaneus and extend into the dorsal aponeurosis of digits one to four, just beyond the penultimate joints. They act to dorsiflex the digits. Similar to the intrinsic muscles of the hand, there are three groups of muscles in

2652-429: The foot. The tibia and fibula and the interosseous membrane separate these muscles into anterior and posterior groups, in their turn subdivided into subgroups and layers. Extensor group : the tibialis anterior originates on the proximal half of the tibia and the interosseous membrane and is inserted near the tarsometatarsal joint of the first digit. In the non-weight-bearing leg, the tibialis anterior dorsiflexes

2720-476: The gait, the knee will generally, but not always, track laterally of the hallux . Like an overpronator, an underpronator does not absorb shock efficiently – but for the opposite reason. The underpronated foot is like a diving board that, instead of failing to spring someone in the air because it is too flimsy, fails to do so because it is too rigid. There is virtually no give. An underpronator's arches or ankles do not experience much motion as they cycle through

2788-401: The gait. An individual whose bone structure involves internal rotation at the hip, knee, or ankle will be more likely to underpronate than one whose bone structure has external rotation or central alignment. Usually – but not always – those who are bow-legged tend to underpronate. An individual who underpronates tends to wear down their running shoes on the lateral (outside) side of

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2856-419: The gene mutation isn't inherited, but a new mutation . Diagnosis may be made on physical features alone, if a person has an arm or hand bone abnormality and a personal or family history of heart problems. If the symptoms aren't enough to diagnose, a person may undergo genetic testing for the mutations associated with the syndrome. A person with Holt-Oram syndrome may need various treatments, depending on how

2924-400: The ground on the lateral side of the heel . As the individual transfers weight from the heel to the metatarsus , the foot will roll in a medial direction, such that the weight is distributed evenly across the metatarsus. In this stage of the gait, the knee will generally, but not always, track directly over the hallux . This rolling inward motion as the foot progresses from heel to toe

2992-406: The hand are possible: abduction (movement towards the radius, so called radial deviation or abduction) of 15 degrees and adduction (movement towards the ulna, so called ulnar deviation or adduction) of 40 degrees when the arm is in strict supination and slightly greater in strict pronation . Flexion (tilting towards the palm, so called palmar flexion) and extension (tilting towards

3060-409: The inside foot. An individual who underpronates also initially strikes the ground on the lateral side of the heel. As the individual transfers weight from the heel to the metatarsus, the foot will not roll far enough in a medial direction. The weight is distributed unevenly across the metatarsus, with excessive weight borne on the fifth metatarsal , toward the lateral side of the foot. In this stage of

3128-399: The knee, assisted by the plantaris. In the deep layer of posterior muscles, the tibialis posterior arises proximally on the back of the interosseous membrane and adjoining bones, and divides into two parts in the sole of the foot to attach to the tarsus. In the non-weight-bearing leg, it produces plantar flexion and supination, and, in the weight-bearing leg, it proximates the heel to

3196-445: The lateral malleolus . Distally, the peroneus longus crosses the plantar side of the foot to reach its insertion on the first tarsometatarsal joint, while the peroneus brevis reaches the proximal part of the fifth metatarsal. These two muscles are the strongest pronators and aid in plantar flexion. The peroneus longus also acts like a bowstring that braces the transverse arch of the foot. The superficial layer of posterior leg muscles

3264-425: The lateral margin of the flexor digitorum tendon. It is also known as the flexor accessorius. The flexor digitorum brevis arises inferiorly on the calcaneus and its three tendons are inserted into the middle phalanges of digits two to four (sometimes also the fifth digit). These tendons divide before their insertions and the tendons of flexor digitorum longus pass through these divisions. Flexor digitorum brevis flexes

3332-405: The lower back). For the sake of posture, flat soles with no heels are advised. A doctor who specializes in the treatment of the feet practices podiatry and is called a podiatrist. A pedorthist specializes in the use and modification of footwear to treat problems related to the lower limbs. Fractures of the foot include: In anatomy, pronation is a rotational movement of the forearm (at

3400-498: The lower chambers of the heart ( ventricular septal defect ). People with Holt–Oram syndrome may also have abnormalities in the electrical system that coordinates contractions of the heart chambers . Cardiac conduction disease can lead to slow heart rate ( bradycardia ); rapid, ineffective contraction of the heart muscles ( fibrillation ); and heart block . People with Holt-Oram syndrome may have only congenital heart defects, only cardiac conduction disease, both or neither. Mutations in

3468-409: The medial (inside) side of the shoe toward the toe area. When choosing a running or walking shoe, a person with overpronation can choose shoes that have good inside support—usually by strong material at the inside sole and arch of the shoe. It is usually visible. The inside support area is marked by strong greyish material to support the weight when a person lands on the outside foot and then roll onto

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3536-412: The medial cuneiform bone and related ligaments and tendons. An important plantar flexor, it is crucial to ballet dancing. Both these muscles are inserted with two heads proximally and distally to the first metatarsophalangeal joint . The adductor hallucis is part of this group, though it originally formed a separate system (see contrahens ). It has two heads, the oblique head originating obliquely across

3604-644: The middle phalanges. It is occasionally absent. Between the toes, the dorsal and plantar interossei stretch from the metatarsals to the proximal phalanges of digits two to five. The plantar interossei adduct and the dorsal interossei abduct these digits, and are also plantar flexors at the metatarsophalangeal joints. Due to their position and function, feet are exposed to a variety of potential infections and injuries , including athlete's foot , bunions , ingrown toenails , Morton's neuroma , plantar fasciitis , plantar warts , and stress fractures . In addition, there are several genetic disorders that can affect

3672-443: The ossific centers appear only after birth. The formation of these centers roughly follows a chronological spiral pattern starting in the capitate and hamate during the first year of life. The ulnar bones are then ossified before the radial bones, while the sesamoid pisiform arises in the tendon of the flexor carpi ulnaris after more than ten years. The commencement of ossification for each bone occurs over period like other bones. This

3740-502: The person to plunge straight down into the water instead of back into the air. Similarly, an overpronator's arches will collapse, or the ankles will roll inward (or a combination of the two) as they cycle through the gait. An individual whose bone structure involves external rotation at the hip , knee, or ankle will be more likely to overpronate than one whose bone structure has internal rotation or central alignment. An individual who overpronates tends to wear down their running shoes on

3808-436: The radioulnar joint) or foot (at the subtalar and talocalcaneonavicular joints). Pronation of the foot refers to how the body distributes weight as it cycles through the gait . During the gait cycle the foot can pronate in many different ways based on rearfoot and forefoot function. Types of pronation include neutral pronation, underpronation (supination), and overpronation. An individual who neutrally pronates initially strikes

3876-572: The radius. During radial abduction the pisiform traverses the greatest path of all carpal bones. Radial abduction is produced by (in order of importance) extensor carpi radialis longus , abductor pollicis longus , extensor pollicis longus , flexor carpi radialis , and flexor pollicis longus . Ulnar adduction causes a tilting or dorsal shifting of the proximal row of carpal bones. It is produced by extensor carpi ulnaris , flexor carpi ulnaris , extensor digitorum , and extensor digiti minimi . Both radial abduction and ulnar adduction occurs around

3944-522: The rest of the metacarpus. The word "foot" is used to refer to a "...linear measure was in Old English (the exact length has varied over time), this being considered the length of a man's foot; a unit of measure used widely and anciently. In this sense the plural is often foot. The current inch and foot are implied from measurements in 12c." The word "foot" also has a musical meaning; a "...metrical foot (late Old English, translating Latin pes, Greek pous in

4012-426: The rigid carpal tunnel which allows the median nerve and tendons of the anterior forearm muscles to be transmitted to the hand and fingers . In tetrapods , the carpus is the sole cluster of bones in the wrist between the radius and ulna and the metacarpus . The bones of the carpus do not belong to individual fingers (or toes in quadrupeds), whereas those of the metacarpus do. The corresponding part of

4080-473: The same sense) is commonly taken to represent one rise and one fall of a foot: keeping time according to some, dancing according to others." The word "foot" was used in Middle English to mean "a person" (c. 1200). The expression "...to put one's best foot foremost first recorded 1849 (Shakespeare has the better foot before, 1596)". The expression to "...put one's foot in (one's) mouth "say something stupid"

4148-452: The scaphoid and lunar bones are fused into the scapholunar bone. In crustaceans , "carpus" is the scientific term for the claws or "pincers" present on some legs. (See Decapod anatomy ) The Latin word "carpus" is derived from Greek καρπὁς meaning "wrist". The root "carp-" translates to " pluck ", an action performed by the wrist. Foot The foot ( pl. : feet ) is an anatomical structure found in many vertebrates . It

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4216-400: The shape and function of the feet, including clubfoot or flat feet . This leaves humans more vulnerable to medical problems that are caused by poor leg and foot alignments. Also, the wearing of shoes, sneakers and boots can impede proper alignment and movement within the ankle and foot. For example, high-heeled shoes are known to throw off the natural weight balance (this can also affect

4284-419: The shoe toward the rear of the shoe in the heel area. Humans usually wear shoes or similar footwear for protection from hazards when walking outside. There are a number of contexts where it is considered inappropriate to wear shoes. Some people consider it rude to wear shoes into a house and sacred places in multiple cultures like Māori Marae , which should only be entered with bare feet. Foot fetishism

4352-450: The syndrome manifests. Surgery, prosthetics and physical or occupational therapy can help people with bone abnormalities. Heart defects may call for surgery, medication, pacemakers or close monitoring. Pregnant women with Holt-Oram syndrome and heart abnormalities should be followed by a cardiologist during pregnancy. It is named for Mary Holt and Samuel Oram, who published a paper on it in 1960. Carpal bones The carpal bones are

4420-402: The thumb and index finger). The structure of the carpus varies widely between different groups of tetrapods , even among those that retain the full set of five digits. In primitive fossil amphibians , such as Eryops , the carpus consists of three rows of bones; a proximal row of three carpals, a second row of four bones, and a distal row of five bones. The proximal carpals are referred to as

4488-409: The trapezium and the trapezoid. In contrast, the distal row is more rigid as its transverse arch moves with the metacarpals . Biomechanically and clinically, the carpal bones are better conceptualized as three longitudinal columns: In this context the pisiform is regarded as a sesamoid bone embedded in the tendon of the flexor carpi ulnaris . The ulnar column leaves a gap between the ulna and

4556-459: The triquetrum, and therefore, only the radial or scaphoid and central or capitate columns articulate with the radius. The wrist is more stable in flexion than in extension more because of the strength of various capsules and ligaments than the interlocking parts of the skeleton. Almost all carpals (except the pisiform) have six surfaces. Of these the palmar or anterior and the dorsal or posterior surfaces are rough, for ligamentous attachment;

4624-436: The vast majority of later vertebrates , including modern amphibians , have undergone varying degrees of loss and fusion of these primitive bones, resulting in a smaller number of carpals. Almost all mammals and reptiles , for example, have lost the fifth distal carpal, and have only a single centrale - and even this is missing in humans. The pisiform bone is somewhat unusual, in that it first appears in primitive reptiles, and

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